{smcl}
{com}{sf}{ul off}{txt}{.-}
      name:  {res}<unnamed>
       {txt}log:  {res}D:\Research\Elicitation effects\VZ analysis (log).smcl
  {txt}log type:  {res}smcl
 {txt}opened on:  {res}28 Sep 2019, 15:19:09

{com}. do "C:\Users\cvossler\AppData\Local\Temp\STD28c4_000000.tmp"
{txt}
{com}. /*This do-file replicates results presented in Christian A. Vossler and Ewa Zawojska, 
> "Behvavioral drivers or economic incentives? Toward a better understanding of elicitation effects in stated preference studies", 
> Journal of the Association of Environmental and Resource Economists */
. 
. *For questions, contact Christian Vossler (cvossler@utk.edu)
. *The name of the public use data file is "VZ data (public).dta"
. 
. ***Table 1: Summary Statistics by Treatment
. sum Age Female EarnedIncome Employed GPA Comprehension Confusion NeedInformation Certainty if SBC==1

{txt}    Variable {c |}        Obs        Mean    Std. Dev.       Min        Max
{hline 13}{c +}{hline 57}
{space 9}Age {c |}{res}        130    20.64615    3.305766         18         40
{txt}{space 6}Female {c |}{res}        130    .4538462    .4997913          0          1
{txt}EarnedIncome {c |}{res}        130    19.76923    3.541643         15         25
{txt}{space 4}Employed {c |}{res}        130    .4615385     .500447          0          1
{txt}{space 9}GPA {c |}{res}        130    3.190385    .5653117          1       3.75
{txt}{hline 13}{c +}{hline 57}
Comprehens~n {c |}{res}        130         4.9    .3011605          4          5
{txt}{space 3}Confusion {c |}{res}        130    1.346154    .7335962          1          5
{txt}NeedInform~n {c |}{res}        130    1.892308    1.122333          1          5
{txt}{space 3}Certainty {c |}{res}        130    4.076923    .9852823          1          5
{txt}
{com}. sum Age Female EarnedIncome Employed GPA Comprehension Confusion NeedInformation Certainty if DB==1

{txt}    Variable {c |}        Obs        Mean    Std. Dev.       Min        Max
{hline 13}{c +}{hline 57}
{space 9}Age {c |}{res}         92    20.80435    2.794182         18         35
{txt}{space 6}Female {c |}{res}         92    .4130435    .4950785          0          1
{txt}EarnedIncome {c |}{res}         92    19.83696    3.492621         15         25
{txt}{space 4}Employed {c |}{res}         92     .576087    .4968847          0          1
{txt}{space 9}GPA {c |}{res}         92    3.339674    .4980477          1       3.75
{txt}{hline 13}{c +}{hline 57}
Comprehens~n {c |}{res}         92    4.880435    .3583353          3          5
{txt}{space 3}Confusion {c |}{res}         92     1.51087    .8832329          1          4
{txt}NeedInform~n {c |}{res}         92    1.771739     .890774          1          4
{txt}{space 3}Certainty {c |}{res}         92    4.141304    .9088275          1          5
{txt}
{com}. sum Age Female EarnedIncome Employed GPA Comprehension Confusion NeedInformation Certainty if PC==1

{txt}    Variable {c |}        Obs        Mean    Std. Dev.       Min        Max
{hline 13}{c +}{hline 57}
{space 9}Age {c |}{res}         94    20.53191    2.284601         18         32
{txt}{space 6}Female {c |}{res}         94    .3723404    .4860205          0          1
{txt}EarnedIncome {c |}{res}         94    19.78723    3.490763         15         25
{txt}{space 4}Employed {c |}{res}         94    .4680851    .5016559          0          1
{txt}{space 9}GPA {c |}{res}         94    3.215426    .5021474          1       3.75
{txt}{hline 13}{c +}{hline 57}
Comprehens~n {c |}{res}         94    4.787234    .5461958          2          5
{txt}{space 3}Confusion {c |}{res}         94    1.702128    1.124792          1          5
{txt}NeedInform~n {c |}{res}         94    2.095745    1.312218          1          5
{txt}{space 3}Certainty {c |}{res}         94    4.021277    1.135722          1          5
{txt}
{com}. sum Age Female EarnedIncome Employed GPA Comprehension Confusion NeedInformation Certainty if OE==1

{txt}    Variable {c |}        Obs        Mean    Std. Dev.       Min        Max
{hline 13}{c +}{hline 57}
{space 9}Age {c |}{res}         94    20.78723    1.508915         18         25
{txt}{space 6}Female {c |}{res}         94    .4787234    .5022257          0          1
{txt}EarnedIncome {c |}{res}         94    19.78723    3.490763         15         25
{txt}{space 4}Employed {c |}{res}         94    .4787234    .5022257          0          1
{txt}{space 9}GPA {c |}{res}         94    3.361702    .4285149       2.25       3.75
{txt}{hline 13}{c +}{hline 57}
Comprehens~n {c |}{res}         94    4.787234    .4835429          3          5
{txt}{space 3}Confusion {c |}{res}         94    1.542553    .9909797          1          4
{txt}NeedInform~n {c |}{res}         94    1.957447    1.153908          1          5
{txt}{space 3}Certainty {c |}{res}         94    3.776596    1.127889          1          5
{txt}
{com}. 
. ***Various tests based on Table 1 data
. ttest Age if PC==1 | SBC==1, by(PC)

{txt}Two-sample t test with equal variances
{hline 9}{c TT}{hline 68}
   Group{col 10}{c |}{col 16}Obs{col 27}Mean{col 35}Std. Err.{col 47}Std. Dev.{col 59}[95% Conf. Interval]
{hline 9}{c +}{hline 68}
       0 {c |}{res}{col 12}    130{col 22} 20.64615{col 34} .2899348{col 46} 3.305766{col 58} 20.07251{col 70}  21.2198
       {txt}1 {c |}{res}{col 12}     94{col 22} 20.53191{col 34} .2356386{col 46} 2.284601{col 58} 20.06398{col 70} 20.99985
{txt}{hline 9}{c +}{hline 68}
combined {c |}{res}{col 12}    224{col 22} 20.59821{col 34} .1948159{col 46} 2.915737{col 58}  20.2143{col 70} 20.98213
{txt}{hline 9}{c +}{hline 68}
    diff {c |}{res}{col 22}  .114239{col 34} .3955771{col 58}-.6653277{col 70} .8938056
{txt}{hline 9}{c BT}{hline 68}
    diff = mean({res}0{txt}) - mean({res}1{txt})                                      t = {res}  0.2888
{txt}Ho: diff = 0                                     degrees of freedom = {res}     222

    {txt}Ha: diff < 0                 Ha: diff != 0                 Ha: diff > 0
 Pr(T < t) = {res}0.6135         {txt}Pr(|T| > |t|) = {res}0.7730          {txt}Pr(T > t) = {res}0.3865
{txt}
{com}. ttest Age if PC==1 | OE==1, by(PC)

{txt}Two-sample t test with equal variances
{hline 9}{c TT}{hline 68}
   Group{col 10}{c |}{col 16}Obs{col 27}Mean{col 35}Std. Err.{col 47}Std. Dev.{col 59}[95% Conf. Interval]
{hline 9}{c +}{hline 68}
       0 {c |}{res}{col 12}     94{col 22} 20.78723{col 34} .1556327{col 46} 1.508915{col 58} 20.47818{col 70} 21.09629
       {txt}1 {c |}{res}{col 12}     94{col 22} 20.53191{col 34} .2356386{col 46} 2.284601{col 58} 20.06398{col 70} 20.99985
{txt}{hline 9}{c +}{hline 68}
combined {c |}{res}{col 12}    188{col 22} 20.65957{col 34} .1411287{col 46} 1.935059{col 58} 20.38117{col 70} 20.93798
{txt}{hline 9}{c +}{hline 68}
    diff {c |}{res}{col 22} .2553191{col 34} .2823952{col 58}-.3017902{col 70} .8124285
{txt}{hline 9}{c BT}{hline 68}
    diff = mean({res}0{txt}) - mean({res}1{txt})                                      t = {res}  0.9041
{txt}Ho: diff = 0                                     degrees of freedom = {res}     186

    {txt}Ha: diff < 0                 Ha: diff != 0                 Ha: diff > 0
 Pr(T < t) = {res}0.8164         {txt}Pr(|T| > |t|) = {res}0.3671          {txt}Pr(T > t) = {res}0.1836
{txt}
{com}. ttest Age if PC==1 | DB==1, by(PC)

{txt}Two-sample t test with equal variances
{hline 9}{c TT}{hline 68}
   Group{col 10}{c |}{col 16}Obs{col 27}Mean{col 35}Std. Err.{col 47}Std. Dev.{col 59}[95% Conf. Interval]
{hline 9}{c +}{hline 68}
       0 {c |}{res}{col 12}     92{col 22} 20.80435{col 34} .2913136{col 46} 2.794182{col 58} 20.22569{col 70} 21.38301
       {txt}1 {c |}{res}{col 12}     94{col 22} 20.53191{col 34} .2356386{col 46} 2.284601{col 58} 20.06398{col 70} 20.99985
{txt}{hline 9}{c +}{hline 68}
combined {c |}{res}{col 12}    186{col 22} 20.66667{col 34} .1866928{col 46} 2.546151{col 58} 20.29835{col 70} 21.03499
{txt}{hline 9}{c +}{hline 68}
    diff {c |}{res}{col 22} .2724329{col 34} .3738815{col 58} -.465213{col 70} 1.010079
{txt}{hline 9}{c BT}{hline 68}
    diff = mean({res}0{txt}) - mean({res}1{txt})                                      t = {res}  0.7287
{txt}Ho: diff = 0                                     degrees of freedom = {res}     184

    {txt}Ha: diff < 0                 Ha: diff != 0                 Ha: diff > 0
 Pr(T < t) = {res}0.7664         {txt}Pr(|T| > |t|) = {res}0.4671          {txt}Pr(T > t) = {res}0.2336
{txt}
{com}. ttest Age if SBC==1 | OE==1, by(SBC)

{txt}Two-sample t test with equal variances
{hline 9}{c TT}{hline 68}
   Group{col 10}{c |}{col 16}Obs{col 27}Mean{col 35}Std. Err.{col 47}Std. Dev.{col 59}[95% Conf. Interval]
{hline 9}{c +}{hline 68}
       0 {c |}{res}{col 12}     94{col 22} 20.78723{col 34} .1556327{col 46} 1.508915{col 58} 20.47818{col 70} 21.09629
       {txt}1 {c |}{res}{col 12}    130{col 22} 20.64615{col 34} .2899348{col 46} 3.305766{col 58} 20.07251{col 70}  21.2198
{txt}{hline 9}{c +}{hline 68}
combined {c |}{res}{col 12}    224{col 22} 20.70536{col 34} .1802283{col 46} 2.697411{col 58} 20.35019{col 70} 21.06053
{txt}{hline 9}{c +}{hline 68}
    diff {c |}{res}{col 22} .1410802{col 34} .3659031{col 58}-.5800077{col 70} .8621681
{txt}{hline 9}{c BT}{hline 68}
    diff = mean({res}0{txt}) - mean({res}1{txt})                                      t = {res}  0.3856
{txt}Ho: diff = 0                                     degrees of freedom = {res}     222

    {txt}Ha: diff < 0                 Ha: diff != 0                 Ha: diff > 0
 Pr(T < t) = {res}0.6499         {txt}Pr(|T| > |t|) = {res}0.7002          {txt}Pr(T > t) = {res}0.3501
{txt}
{com}. ttest Age if SBC==1 | DB==1, by(SBC)

{txt}Two-sample t test with equal variances
{hline 9}{c TT}{hline 68}
   Group{col 10}{c |}{col 16}Obs{col 27}Mean{col 35}Std. Err.{col 47}Std. Dev.{col 59}[95% Conf. Interval]
{hline 9}{c +}{hline 68}
       0 {c |}{res}{col 12}     92{col 22} 20.80435{col 34} .2913136{col 46} 2.794182{col 58} 20.22569{col 70} 21.38301
       {txt}1 {c |}{res}{col 12}    130{col 22} 20.64615{col 34} .2899348{col 46} 3.305766{col 58} 20.07251{col 70}  21.2198
{txt}{hline 9}{c +}{hline 68}
combined {c |}{res}{col 12}    222{col 22} 20.71171{col 34} .2079476{col 46}  3.09835{col 58}  20.3019{col 70} 21.12153
{txt}{hline 9}{c +}{hline 68}
    diff {c |}{res}{col 22}  .158194{col 34} .4229491{col 58}-.6753565{col 70} .9917444
{txt}{hline 9}{c BT}{hline 68}
    diff = mean({res}0{txt}) - mean({res}1{txt})                                      t = {res}  0.3740
{txt}Ho: diff = 0                                     degrees of freedom = {res}     220

    {txt}Ha: diff < 0                 Ha: diff != 0                 Ha: diff > 0
 Pr(T < t) = {res}0.6456         {txt}Pr(|T| > |t|) = {res}0.7087          {txt}Pr(T > t) = {res}0.3544
{txt}
{com}. ttest Age if OE==1 | DB==1, by(OE)

{txt}Two-sample t test with equal variances
{hline 9}{c TT}{hline 68}
   Group{col 10}{c |}{col 16}Obs{col 27}Mean{col 35}Std. Err.{col 47}Std. Dev.{col 59}[95% Conf. Interval]
{hline 9}{c +}{hline 68}
       0 {c |}{res}{col 12}     92{col 22} 20.80435{col 34} .2913136{col 46} 2.794182{col 58} 20.22569{col 70} 21.38301
       {txt}1 {c |}{res}{col 12}     94{col 22} 20.78723{col 34} .1556327{col 46} 1.508915{col 58} 20.47818{col 70} 21.09629
{txt}{hline 9}{c +}{hline 68}
combined {c |}{res}{col 12}    186{col 22}  20.7957{col 34} .1637114{col 46} 2.232725{col 58} 20.47272{col 70} 21.11868
{txt}{hline 9}{c +}{hline 68}
    diff {c |}{res}{col 22} .0171138{col 34} .3283278{col 58}-.6306575{col 70}  .664885
{txt}{hline 9}{c BT}{hline 68}
    diff = mean({res}0{txt}) - mean({res}1{txt})                                      t = {res}  0.0521
{txt}Ho: diff = 0                                     degrees of freedom = {res}     184

    {txt}Ha: diff < 0                 Ha: diff != 0                 Ha: diff > 0
 Pr(T < t) = {res}0.5208         {txt}Pr(|T| > |t|) = {res}0.9585          {txt}Pr(T > t) = {res}0.4792
{txt}
{com}. 
. tabulate Female PC if PC==1 | SBC==1, exact

     {txt}=1 if {c |}
participan {c |}  =1 for payment card
      t is {c |}      elicitation
    female {c |}         0          1 {c |}     Total
{hline 11}{c +}{hline 22}{c +}{hline 10}
         0 {c |}{res}        71         59 {txt}{c |}{res}       130 
{txt}         1 {c |}{res}        59         35 {txt}{c |}{res}        94 
{txt}{hline 11}{c +}{hline 22}{c +}{hline 10}
     Total {c |}{res}       130         94 {txt}{c |}{res}       224 

{txt}           Fisher's exact =                 {res}0.272
{txt}   1-sided Fisher's exact =                 {res}0.139
{txt}
{com}. tabulate Female PC if PC==1 | OE==1, exact

     {txt}=1 if {c |}
participan {c |}  =1 for payment card
      t is {c |}      elicitation
    female {c |}         0          1 {c |}     Total
{hline 11}{c +}{hline 22}{c +}{hline 10}
         0 {c |}{res}        49         59 {txt}{c |}{res}       108 
{txt}         1 {c |}{res}        45         35 {txt}{c |}{res}        80 
{txt}{hline 11}{c +}{hline 22}{c +}{hline 10}
     Total {c |}{res}        94         94 {txt}{c |}{res}       188 

{txt}           Fisher's exact =                 {res}0.184
{txt}   1-sided Fisher's exact =                 {res}0.092
{txt}
{com}. tabulate Female PC if PC==1 | DB==1, exact

     {txt}=1 if {c |}
participan {c |}  =1 for payment card
      t is {c |}      elicitation
    female {c |}         0          1 {c |}     Total
{hline 11}{c +}{hline 22}{c +}{hline 10}
         0 {c |}{res}        54         59 {txt}{c |}{res}       113 
{txt}         1 {c |}{res}        38         35 {txt}{c |}{res}        73 
{txt}{hline 11}{c +}{hline 22}{c +}{hline 10}
     Total {c |}{res}        92         94 {txt}{c |}{res}       186 

{txt}           Fisher's exact =                 {res}0.653
{txt}   1-sided Fisher's exact =                 {res}0.338
{txt}
{com}. tabulate Female SBC if SBC==1 | OE==1, exact

     {txt}=1 if {c |}
participan {c |} =1 for single binary
      t is {c |}   choice eliciation
    female {c |}         0          1 {c |}     Total
{hline 11}{c +}{hline 22}{c +}{hline 10}
         0 {c |}{res}        49         71 {txt}{c |}{res}       120 
{txt}         1 {c |}{res}        45         59 {txt}{c |}{res}       104 
{txt}{hline 11}{c +}{hline 22}{c +}{hline 10}
     Total {c |}{res}        94        130 {txt}{c |}{res}       224 

{txt}           Fisher's exact =                 {res}0.786
{txt}   1-sided Fisher's exact =                 {res}0.408
{txt}
{com}. tabulate Female SBC if SBC==1 | DB==1, exact

     {txt}=1 if {c |}
participan {c |} =1 for single binary
      t is {c |}   choice eliciation
    female {c |}         0          1 {c |}     Total
{hline 11}{c +}{hline 22}{c +}{hline 10}
         0 {c |}{res}        54         71 {txt}{c |}{res}       125 
{txt}         1 {c |}{res}        38         59 {txt}{c |}{res}        97 
{txt}{hline 11}{c +}{hline 22}{c +}{hline 10}
     Total {c |}{res}        92        130 {txt}{c |}{res}       222 

{txt}           Fisher's exact =                 {res}0.584
{txt}   1-sided Fisher's exact =                 {res}0.321
{txt}
{com}. tabulate Female OE if OE==1 | DB==1, exact

     {txt}=1 if {c |}
participan {c |}   =1 for open ended
      t is {c |}      elicitaiton
    female {c |}         0          1 {c |}     Total
{hline 11}{c +}{hline 22}{c +}{hline 10}
         0 {c |}{res}        54         49 {txt}{c |}{res}       103 
{txt}         1 {c |}{res}        38         45 {txt}{c |}{res}        83 
{txt}{hline 11}{c +}{hline 22}{c +}{hline 10}
     Total {c |}{res}        92         94 {txt}{c |}{res}       186 

{txt}           Fisher's exact =                 {res}0.380
{txt}   1-sided Fisher's exact =                 {res}0.226
{txt}
{com}. 
. tabulate Employed PC if PC==1 | SBC==1, exact

     {txt}=1 if {c |}  =1 for payment card
 employed; {c |}      elicitation
    else=0 {c |}         0          1 {c |}     Total
{hline 11}{c +}{hline 22}{c +}{hline 10}
         0 {c |}{res}        70         50 {txt}{c |}{res}       120 
{txt}         1 {c |}{res}        60         44 {txt}{c |}{res}       104 
{txt}{hline 11}{c +}{hline 22}{c +}{hline 10}
     Total {c |}{res}       130         94 {txt}{c |}{res}       224 

{txt}           Fisher's exact =                 {res}1.000
{txt}   1-sided Fisher's exact =                 {res}0.515
{txt}
{com}. tabulate Employed PC if PC==1 | OE==1, exact

     {txt}=1 if {c |}  =1 for payment card
 employed; {c |}      elicitation
    else=0 {c |}         0          1 {c |}     Total
{hline 11}{c +}{hline 22}{c +}{hline 10}
         0 {c |}{res}        49         50 {txt}{c |}{res}        99 
{txt}         1 {c |}{res}        45         44 {txt}{c |}{res}        89 
{txt}{hline 11}{c +}{hline 22}{c +}{hline 10}
     Total {c |}{res}        94         94 {txt}{c |}{res}       188 

{txt}           Fisher's exact =                 {res}1.000
{txt}   1-sided Fisher's exact =                 {res}0.500
{txt}
{com}. tabulate Employed PC if PC==1 | DB==1, exact

     {txt}=1 if {c |}  =1 for payment card
 employed; {c |}      elicitation
    else=0 {c |}         0          1 {c |}     Total
{hline 11}{c +}{hline 22}{c +}{hline 10}
         0 {c |}{res}        39         50 {txt}{c |}{res}        89 
{txt}         1 {c |}{res}        53         44 {txt}{c |}{res}        97 
{txt}{hline 11}{c +}{hline 22}{c +}{hline 10}
     Total {c |}{res}        92         94 {txt}{c |}{res}       186 

{txt}           Fisher's exact =                 {res}0.146
{txt}   1-sided Fisher's exact =                 {res}0.092
{txt}
{com}. tabulate Employed SBC if SBC==1 | OE==1, exact

     {txt}=1 if {c |} =1 for single binary
 employed; {c |}   choice eliciation
    else=0 {c |}         0          1 {c |}     Total
{hline 11}{c +}{hline 22}{c +}{hline 10}
         0 {c |}{res}        49         70 {txt}{c |}{res}       119 
{txt}         1 {c |}{res}        45         60 {txt}{c |}{res}       105 
{txt}{hline 11}{c +}{hline 22}{c +}{hline 10}
     Total {c |}{res}        94        130 {txt}{c |}{res}       224 

{txt}           Fisher's exact =                 {res}0.892
{txt}   1-sided Fisher's exact =                 {res}0.453
{txt}
{com}. tabulate Employed SBC if SBC==1 | DB==1, exact

     {txt}=1 if {c |} =1 for single binary
 employed; {c |}   choice eliciation
    else=0 {c |}         0          1 {c |}     Total
{hline 11}{c +}{hline 22}{c +}{hline 10}
         0 {c |}{res}        39         70 {txt}{c |}{res}       109 
{txt}         1 {c |}{res}        53         60 {txt}{c |}{res}       113 
{txt}{hline 11}{c +}{hline 22}{c +}{hline 10}
     Total {c |}{res}        92        130 {txt}{c |}{res}       222 

{txt}           Fisher's exact =                 {res}0.103
{txt}   1-sided Fisher's exact =                 {res}0.061
{txt}
{com}. tabulate Employed OE if OE==1 | DB==1, exact

     {txt}=1 if {c |}   =1 for open ended
 employed; {c |}      elicitaiton
    else=0 {c |}         0          1 {c |}     Total
{hline 11}{c +}{hline 22}{c +}{hline 10}
         0 {c |}{res}        39         49 {txt}{c |}{res}        88 
{txt}         1 {c |}{res}        53         45 {txt}{c |}{res}        98 
{txt}{hline 11}{c +}{hline 22}{c +}{hline 10}
     Total {c |}{res}        92         94 {txt}{c |}{res}       186 

{txt}           Fisher's exact =                 {res}0.190
{txt}   1-sided Fisher's exact =                 {res}0.118
{txt}
{com}. 
. tabulate GPA PC if PC==1 | SBC==1, exact

{text}Enumerating sample-space combinations:
{text}stage 5:{col 11}enumerations = 1
{text}stage 4:{col 11}enumerations = 2
{text}stage 3:{col 11}enumerations = 3
{text}stage 2:{col 11}enumerations = 5
{text}stage 1:{col 11}enumerations = 0

Participan {c |}
    t GPA; {c |}
midpont of {c |}  =1 for payment card
    chosen {c |}      elicitation
  interval {c |}         0          1 {c |}     Total
{hline 11}{c +}{hline 22}{c +}{hline 10}
         1 {c |}{res}         3          1 {txt}{c |}{res}         4 
{txt}      2.25 {c |}{res}         9          6 {txt}{c |}{res}        15 
{txt}      2.75 {c |}{res}        27         20 {txt}{c |}{res}        47 
{txt}      3.25 {c |}{res}        48         37 {txt}{c |}{res}        85 
{txt}      3.75 {c |}{res}        43         30 {txt}{c |}{res}        73 
{txt}{hline 11}{c +}{hline 22}{c +}{hline 10}
     Total {c |}{res}       130         94 {txt}{c |}{res}       224 

{txt}           Fisher's exact =                 {res}0.986
{txt}
{com}. tabulate GPA PC if PC==1 | OE==1, exact

{text}Enumerating sample-space combinations:
{text}stage 5:{col 11}enumerations = 1
{text}stage 4:{col 11}enumerations = 1
{text}stage 3:{col 11}enumerations = 7
{text}stage 2:{col 11}enumerations = 51
{text}stage 1:{col 11}enumerations = 0

Participan {c |}
    t GPA; {c |}
midpont of {c |}  =1 for payment card
    chosen {c |}      elicitation
  interval {c |}         0          1 {c |}     Total
{hline 11}{c +}{hline 22}{c +}{hline 10}
         1 {c |}{res}         0          1 {txt}{c |}{res}         1 
{txt}      2.25 {c |}{res}         4          6 {txt}{c |}{res}        10 
{txt}      2.75 {c |}{res}        14         20 {txt}{c |}{res}        34 
{txt}      3.25 {c |}{res}        33         37 {txt}{c |}{res}        70 
{txt}      3.75 {c |}{res}        43         30 {txt}{c |}{res}        73 
{txt}{hline 11}{c +}{hline 22}{c +}{hline 10}
     Total {c |}{res}        94         94 {txt}{c |}{res}       188 

{txt}           Fisher's exact =                 {res}0.268
{txt}
{com}. tabulate GPA PC if PC==1 | DB==1, exact

{text}Enumerating sample-space combinations:
{text}stage 5:{col 11}enumerations = 1
{text}stage 4:{col 11}enumerations = 3
{text}stage 3:{col 11}enumerations = 15
{text}stage 2:{col 11}enumerations = 130
{text}stage 1:{col 11}enumerations = 0

Participan {c |}
    t GPA; {c |}
midpont of {c |}  =1 for payment card
    chosen {c |}      elicitation
  interval {c |}         0          1 {c |}     Total
{hline 11}{c +}{hline 22}{c +}{hline 10}
         1 {c |}{res}         1          1 {txt}{c |}{res}         2 
{txt}      2.25 {c |}{res}         3          6 {txt}{c |}{res}         9 
{txt}      2.75 {c |}{res}        17         20 {txt}{c |}{res}        37 
{txt}      3.25 {c |}{res}        27         37 {txt}{c |}{res}        64 
{txt}      3.75 {c |}{res}        44         30 {txt}{c |}{res}        74 
{txt}{hline 11}{c +}{hline 22}{c +}{hline 10}
     Total {c |}{res}        92         94 {txt}{c |}{res}       186 

{txt}           Fisher's exact =                 {res}0.203
{txt}
{com}. tabulate GPA SBC if SBC==1 | OE==1, exact

{text}Enumerating sample-space combinations:
{text}stage 5:{col 11}enumerations = 1
{text}stage 4:{col 11}enumerations = 4
{text}stage 3:{col 11}enumerations = 25
{text}stage 2:{col 11}enumerations = 202
{text}stage 1:{col 11}enumerations = 0

Participan {c |}
    t GPA; {c |}
midpont of {c |} =1 for single binary
    chosen {c |}   choice eliciation
  interval {c |}         0          1 {c |}     Total
{hline 11}{c +}{hline 22}{c +}{hline 10}
         1 {c |}{res}         0          3 {txt}{c |}{res}         3 
{txt}      2.25 {c |}{res}         4          9 {txt}{c |}{res}        13 
{txt}      2.75 {c |}{res}        14         27 {txt}{c |}{res}        41 
{txt}      3.25 {c |}{res}        33         48 {txt}{c |}{res}        81 
{txt}      3.75 {c |}{res}        43         43 {txt}{c |}{res}        86 
{txt}{hline 11}{c +}{hline 22}{c +}{hline 10}
     Total {c |}{res}        94        130 {txt}{c |}{res}       224 

{txt}           Fisher's exact =                 {res}0.213
{txt}
{com}. tabulate GPA SBC if SBC==1 | DB==1, exact

{text}Enumerating sample-space combinations:
{text}stage 5:{col 11}enumerations = 1
{text}stage 4:{col 11}enumerations = 5
{text}stage 3:{col 11}enumerations = 27
{text}stage 2:{col 11}enumerations = 234
{text}stage 1:{col 11}enumerations = 0

Participan {c |}
    t GPA; {c |}
midpont of {c |} =1 for single binary
    chosen {c |}   choice eliciation
  interval {c |}         0          1 {c |}     Total
{hline 11}{c +}{hline 22}{c +}{hline 10}
         1 {c |}{res}         1          3 {txt}{c |}{res}         4 
{txt}      2.25 {c |}{res}         3          9 {txt}{c |}{res}        12 
{txt}      2.75 {c |}{res}        17         27 {txt}{c |}{res}        44 
{txt}      3.25 {c |}{res}        27         48 {txt}{c |}{res}        75 
{txt}      3.75 {c |}{res}        44         43 {txt}{c |}{res}        87 
{txt}{hline 11}{c +}{hline 22}{c +}{hline 10}
     Total {c |}{res}        92        130 {txt}{c |}{res}       222 

{txt}           Fisher's exact =                 {res}0.223
{txt}
{com}. tabulate GPA OE if OE==1 | DB==1, exact

{text}Enumerating sample-space combinations:
{text}stage 5:{col 11}enumerations = 1
{text}stage 4:{col 11}enumerations = 2
{text}stage 3:{col 11}enumerations = 3
{text}stage 2:{col 11}enumerations = 9
{text}stage 1:{col 11}enumerations = 0

Participan {c |}
    t GPA; {c |}
midpont of {c |}   =1 for open ended
    chosen {c |}      elicitaiton
  interval {c |}         0          1 {c |}     Total
{hline 11}{c +}{hline 22}{c +}{hline 10}
         1 {c |}{res}         1          0 {txt}{c |}{res}         1 
{txt}      2.25 {c |}{res}         3          4 {txt}{c |}{res}         7 
{txt}      2.75 {c |}{res}        17         14 {txt}{c |}{res}        31 
{txt}      3.25 {c |}{res}        27         33 {txt}{c |}{res}        60 
{txt}      3.75 {c |}{res}        44         43 {txt}{c |}{res}        87 
{txt}{hline 11}{c +}{hline 22}{c +}{hline 10}
     Total {c |}{res}        92         94 {txt}{c |}{res}       186 

{txt}           Fisher's exact =                 {res}0.813
{txt}
{com}. 
. ttest Comprehension if PC==1 | SBC==1, by(PC)

{txt}Two-sample t test with equal variances
{hline 9}{c TT}{hline 68}
   Group{col 10}{c |}{col 16}Obs{col 27}Mean{col 35}Std. Err.{col 47}Std. Dev.{col 59}[95% Conf. Interval]
{hline 9}{c +}{hline 68}
       0 {c |}{res}{col 12}    130{col 22}      4.9{col 34} .0264135{col 46} .3011605{col 58}  4.84774{col 70}  4.95226
       {txt}1 {c |}{res}{col 12}     94{col 22} 4.787234{col 34} .0563358{col 46} .5461958{col 58} 4.675362{col 70} 4.899106
{txt}{hline 9}{c +}{hline 68}
combined {c |}{res}{col 12}    224{col 22} 4.852679{col 34} .0283468{col 46} .4242556{col 58} 4.796817{col 70}  4.90854
{txt}{hline 9}{c +}{hline 68}
    diff {c |}{res}{col 22}  .112766{col 34} .0570698{col 58} .0002981{col 70} .2252338
{txt}{hline 9}{c BT}{hline 68}
    diff = mean({res}0{txt}) - mean({res}1{txt})                                      t = {res}  1.9759
{txt}Ho: diff = 0                                     degrees of freedom = {res}     222

    {txt}Ha: diff < 0                 Ha: diff != 0                 Ha: diff > 0
 Pr(T < t) = {res}0.9753         {txt}Pr(|T| > |t|) = {res}0.0494          {txt}Pr(T > t) = {res}0.0247
{txt}
{com}. ttest Comprehension if PC==1 | OE==1, by(PC)

{txt}Two-sample t test with equal variances
{hline 9}{c TT}{hline 68}
   Group{col 10}{c |}{col 16}Obs{col 27}Mean{col 35}Std. Err.{col 47}Std. Dev.{col 59}[95% Conf. Interval]
{hline 9}{c +}{hline 68}
       0 {c |}{res}{col 12}     94{col 22} 4.787234{col 34} .0498736{col 46} .4835429{col 58} 4.688195{col 70} 4.886273
       {txt}1 {c |}{res}{col 12}     94{col 22} 4.787234{col 34} .0563358{col 46} .5461958{col 58} 4.675362{col 70} 4.899106
{txt}{hline 9}{c +}{hline 68}
combined {c |}{res}{col 12}    188{col 22} 4.787234{col 34} .0375194{col 46} .5144405{col 58} 4.713218{col 70}  4.86125
{txt}{hline 9}{c +}{hline 68}
    diff {c |}{res}{col 22}        0{col 34} .0752403{col 58}-.1484341{col 70} .1484341
{txt}{hline 9}{c BT}{hline 68}
    diff = mean({res}0{txt}) - mean({res}1{txt})                                      t = {res}  0.0000
{txt}Ho: diff = 0                                     degrees of freedom = {res}     186

    {txt}Ha: diff < 0                 Ha: diff != 0                 Ha: diff > 0
 Pr(T < t) = {res}0.5000         {txt}Pr(|T| > |t|) = {res}1.0000          {txt}Pr(T > t) = {res}0.5000
{txt}
{com}. ttest Comprehension if PC==1 | DB==1, by(PC)

{txt}Two-sample t test with equal variances
{hline 9}{c TT}{hline 68}
   Group{col 10}{c |}{col 16}Obs{col 27}Mean{col 35}Std. Err.{col 47}Std. Dev.{col 59}[95% Conf. Interval]
{hline 9}{c +}{hline 68}
       0 {c |}{res}{col 12}     92{col 22} 4.880435{col 34}  .037359{col 46} .3583353{col 58} 4.806226{col 70} 4.954644
       {txt}1 {c |}{res}{col 12}     94{col 22} 4.787234{col 34} .0563358{col 46} .5461958{col 58} 4.675362{col 70} 4.899106
{txt}{hline 9}{c +}{hline 68}
combined {c |}{res}{col 12}    186{col 22} 4.833333{col 34} .0340237{col 46} .4640208{col 58} 4.766209{col 70} 4.900458
{txt}{hline 9}{c +}{hline 68}
    diff {c |}{res}{col 22} .0932007{col 34} .0678891{col 58}-.0407404{col 70} .2271419
{txt}{hline 9}{c BT}{hline 68}
    diff = mean({res}0{txt}) - mean({res}1{txt})                                      t = {res}  1.3728
{txt}Ho: diff = 0                                     degrees of freedom = {res}     184

    {txt}Ha: diff < 0                 Ha: diff != 0                 Ha: diff > 0
 Pr(T < t) = {res}0.9143         {txt}Pr(|T| > |t|) = {res}0.1715          {txt}Pr(T > t) = {res}0.0857
{txt}
{com}. ttest Comprehension if SBC==1 | OE==1, by(SBC)

{txt}Two-sample t test with equal variances
{hline 9}{c TT}{hline 68}
   Group{col 10}{c |}{col 16}Obs{col 27}Mean{col 35}Std. Err.{col 47}Std. Dev.{col 59}[95% Conf. Interval]
{hline 9}{c +}{hline 68}
       0 {c |}{res}{col 12}     94{col 22} 4.787234{col 34} .0498736{col 46} .4835429{col 58} 4.688195{col 70} 4.886273
       {txt}1 {c |}{res}{col 12}    130{col 22}      4.9{col 34} .0264135{col 46} .3011605{col 58}  4.84774{col 70}  4.95226
{txt}{hline 9}{c +}{hline 68}
combined {c |}{res}{col 12}    224{col 22} 4.852679{col 34} .0261424{col 46} .3912633{col 58} 4.801161{col 70} 4.904196
{txt}{hline 9}{c +}{hline 68}
    diff {c |}{res}{col 22} -.112766{col 34} .0525503{col 58}-.2163273{col 70}-.0092046
{txt}{hline 9}{c BT}{hline 68}
    diff = mean({res}0{txt}) - mean({res}1{txt})                                      t = {res} -2.1459
{txt}Ho: diff = 0                                     degrees of freedom = {res}     222

    {txt}Ha: diff < 0                 Ha: diff != 0                 Ha: diff > 0
 Pr(T < t) = {res}0.0165         {txt}Pr(|T| > |t|) = {res}0.0330          {txt}Pr(T > t) = {res}0.9835
{txt}
{com}. ttest Comprehension if SBC==1 | DB==1, by(SBC)

{txt}Two-sample t test with equal variances
{hline 9}{c TT}{hline 68}
   Group{col 10}{c |}{col 16}Obs{col 27}Mean{col 35}Std. Err.{col 47}Std. Dev.{col 59}[95% Conf. Interval]
{hline 9}{c +}{hline 68}
       0 {c |}{res}{col 12}     92{col 22} 4.880435{col 34}  .037359{col 46} .3583353{col 58} 4.806226{col 70} 4.954644
       {txt}1 {c |}{res}{col 12}    130{col 22}      4.9{col 34} .0264135{col 46} .3011605{col 58}  4.84774{col 70}  4.95226
{txt}{hline 9}{c +}{hline 68}
combined {c |}{res}{col 12}    222{col 22} 4.891892{col 34} .0218417{col 46} .3254333{col 58} 4.848847{col 70} 4.934936
{txt}{hline 9}{c +}{hline 68}
    diff {c |}{res}{col 22}-.0195652{col 34} .0444187{col 58}-.1071059{col 70} .0679755
{txt}{hline 9}{c BT}{hline 68}
    diff = mean({res}0{txt}) - mean({res}1{txt})                                      t = {res} -0.4405
{txt}Ho: diff = 0                                     degrees of freedom = {res}     220

    {txt}Ha: diff < 0                 Ha: diff != 0                 Ha: diff > 0
 Pr(T < t) = {res}0.3300         {txt}Pr(|T| > |t|) = {res}0.6600          {txt}Pr(T > t) = {res}0.6700
{txt}
{com}. ttest Comprehension if OE==1 | DB==1, by(OE)

{txt}Two-sample t test with equal variances
{hline 9}{c TT}{hline 68}
   Group{col 10}{c |}{col 16}Obs{col 27}Mean{col 35}Std. Err.{col 47}Std. Dev.{col 59}[95% Conf. Interval]
{hline 9}{c +}{hline 68}
       0 {c |}{res}{col 12}     92{col 22} 4.880435{col 34}  .037359{col 46} .3583353{col 58} 4.806226{col 70} 4.954644
       {txt}1 {c |}{res}{col 12}     94{col 22} 4.787234{col 34} .0498736{col 46} .4835429{col 58} 4.688195{col 70} 4.886273
{txt}{hline 9}{c +}{hline 68}
combined {c |}{res}{col 12}    186{col 22} 4.833333{col 34} .0313567{col 46} .4276481{col 58} 4.771471{col 70} 4.895196
{txt}{hline 9}{c +}{hline 68}
    diff {c |}{res}{col 22} .0932007{col 34} .0625107{col 58}-.0301292{col 70} .2165307
{txt}{hline 9}{c BT}{hline 68}
    diff = mean({res}0{txt}) - mean({res}1{txt})                                      t = {res}  1.4910
{txt}Ho: diff = 0                                     degrees of freedom = {res}     184

    {txt}Ha: diff < 0                 Ha: diff != 0                 Ha: diff > 0
 Pr(T < t) = {res}0.9312         {txt}Pr(|T| > |t|) = {res}0.1377          {txt}Pr(T > t) = {res}0.0688
{txt}
{com}. 
. ttest Confusion if PC==1 | SBC==1, by(PC)

{txt}Two-sample t test with equal variances
{hline 9}{c TT}{hline 68}
   Group{col 10}{c |}{col 16}Obs{col 27}Mean{col 35}Std. Err.{col 47}Std. Dev.{col 59}[95% Conf. Interval]
{hline 9}{c +}{hline 68}
       0 {c |}{res}{col 12}    130{col 22} 1.346154{col 34} .0643406{col 46} .7335962{col 58} 1.218854{col 70} 1.473453
       {txt}1 {c |}{res}{col 12}     94{col 22} 1.702128{col 34} .1160134{col 46} 1.124792{col 58} 1.471748{col 70} 1.932507
{txt}{hline 9}{c +}{hline 68}
combined {c |}{res}{col 12}    224{col 22} 1.495536{col 34} .0623188{col 46} .9327031{col 58} 1.372727{col 70} 1.618345
{txt}{hline 9}{c +}{hline 68}
    diff {c |}{res}{col 22}-.3559738{col 34} .1242879{col 58}-.6009088{col 70}-.1110388
{txt}{hline 9}{c BT}{hline 68}
    diff = mean({res}0{txt}) - mean({res}1{txt})                                      t = {res} -2.8641
{txt}Ho: diff = 0                                     degrees of freedom = {res}     222

    {txt}Ha: diff < 0                 Ha: diff != 0                 Ha: diff > 0
 Pr(T < t) = {res}0.0023         {txt}Pr(|T| > |t|) = {res}0.0046          {txt}Pr(T > t) = {res}0.9977
{txt}
{com}. ttest Confusion if PC==1 | OE==1, by(PC)

{txt}Two-sample t test with equal variances
{hline 9}{c TT}{hline 68}
   Group{col 10}{c |}{col 16}Obs{col 27}Mean{col 35}Std. Err.{col 47}Std. Dev.{col 59}[95% Conf. Interval]
{hline 9}{c +}{hline 68}
       0 {c |}{res}{col 12}     94{col 22} 1.542553{col 34} .1022117{col 46} .9909797{col 58} 1.339581{col 70} 1.745525
       {txt}1 {c |}{res}{col 12}     94{col 22} 1.702128{col 34} .1160134{col 46} 1.124792{col 58} 1.471748{col 70} 1.932507
{txt}{hline 9}{c +}{hline 68}
combined {c |}{res}{col 12}    188{col 22}  1.62234{col 34} .0773219{col 46} 1.060184{col 58} 1.469805{col 70} 1.774876
{txt}{hline 9}{c +}{hline 68}
    diff {c |}{res}{col 22}-.1595745{col 34} .1546168{col 58}-.4646025{col 70} .1454536
{txt}{hline 9}{c BT}{hline 68}
    diff = mean({res}0{txt}) - mean({res}1{txt})                                      t = {res} -1.0321
{txt}Ho: diff = 0                                     degrees of freedom = {res}     186

    {txt}Ha: diff < 0                 Ha: diff != 0                 Ha: diff > 0
 Pr(T < t) = {res}0.1517         {txt}Pr(|T| > |t|) = {res}0.3034          {txt}Pr(T > t) = {res}0.8483
{txt}
{com}. ttest Confusion if PC==1 | DB==1, by(PC)

{txt}Two-sample t test with equal variances
{hline 9}{c TT}{hline 68}
   Group{col 10}{c |}{col 16}Obs{col 27}Mean{col 35}Std. Err.{col 47}Std. Dev.{col 59}[95% Conf. Interval]
{hline 9}{c +}{hline 68}
       0 {c |}{res}{col 12}     92{col 22}  1.51087{col 34} .0920834{col 46} .8832329{col 58} 1.327957{col 70} 1.693782
       {txt}1 {c |}{res}{col 12}     94{col 22} 1.702128{col 34} .1160134{col 46} 1.124792{col 58} 1.471748{col 70} 1.932507
{txt}{hline 9}{c +}{hline 68}
combined {c |}{res}{col 12}    186{col 22} 1.607527{col 34} .0743761{col 46} 1.014355{col 58} 1.460792{col 70} 1.754261
{txt}{hline 9}{c +}{hline 68}
    diff {c |}{res}{col 22}-.1912581{col 34} .1484966{col 58}-.4842331{col 70}  .101717
{txt}{hline 9}{c BT}{hline 68}
    diff = mean({res}0{txt}) - mean({res}1{txt})                                      t = {res} -1.2880
{txt}Ho: diff = 0                                     degrees of freedom = {res}     184

    {txt}Ha: diff < 0                 Ha: diff != 0                 Ha: diff > 0
 Pr(T < t) = {res}0.0997         {txt}Pr(|T| > |t|) = {res}0.1994          {txt}Pr(T > t) = {res}0.9003
{txt}
{com}. ttest Confusion if SBC==1 | OE==1, by(SBC)

{txt}Two-sample t test with equal variances
{hline 9}{c TT}{hline 68}
   Group{col 10}{c |}{col 16}Obs{col 27}Mean{col 35}Std. Err.{col 47}Std. Dev.{col 59}[95% Conf. Interval]
{hline 9}{c +}{hline 68}
       0 {c |}{res}{col 12}     94{col 22} 1.542553{col 34} .1022117{col 46} .9909797{col 58} 1.339581{col 70} 1.745525
       {txt}1 {c |}{res}{col 12}    130{col 22} 1.346154{col 34} .0643406{col 46} .7335962{col 58} 1.218854{col 70} 1.473453
{txt}{hline 9}{c +}{hline 68}
combined {c |}{res}{col 12}    224{col 22} 1.428571{col 34} .0570988{col 46} .8545766{col 58} 1.316049{col 70} 1.541094
{txt}{hline 9}{c +}{hline 68}
    diff {c |}{res}{col 22} .1963993{col 34} .1152103{col 58}-.0306464{col 70} .4234451
{txt}{hline 9}{c BT}{hline 68}
    diff = mean({res}0{txt}) - mean({res}1{txt})                                      t = {res}  1.7047
{txt}Ho: diff = 0                                     degrees of freedom = {res}     222

    {txt}Ha: diff < 0                 Ha: diff != 0                 Ha: diff > 0
 Pr(T < t) = {res}0.9552         {txt}Pr(|T| > |t|) = {res}0.0896          {txt}Pr(T > t) = {res}0.0448
{txt}
{com}. ttest Confusion if SBC==1 | DB==1, by(SBC)

{txt}Two-sample t test with equal variances
{hline 9}{c TT}{hline 68}
   Group{col 10}{c |}{col 16}Obs{col 27}Mean{col 35}Std. Err.{col 47}Std. Dev.{col 59}[95% Conf. Interval]
{hline 9}{c +}{hline 68}
       0 {c |}{res}{col 12}     92{col 22}  1.51087{col 34} .0920834{col 46} .8832329{col 58} 1.327957{col 70} 1.693782
       {txt}1 {c |}{res}{col 12}    130{col 22} 1.346154{col 34} .0643406{col 46} .7335962{col 58} 1.218854{col 70} 1.473453
{txt}{hline 9}{c +}{hline 68}
combined {c |}{res}{col 12}    222{col 22} 1.414414{col 34} .0537748{col 46} .8012261{col 58} 1.308437{col 70} 1.520391
{txt}{hline 9}{c +}{hline 68}
    diff {c |}{res}{col 22} .1647157{col 34} .1088434{col 58}-.0497934{col 70} .3792248
{txt}{hline 9}{c BT}{hline 68}
    diff = mean({res}0{txt}) - mean({res}1{txt})                                      t = {res}  1.5133
{txt}Ho: diff = 0                                     degrees of freedom = {res}     220

    {txt}Ha: diff < 0                 Ha: diff != 0                 Ha: diff > 0
 Pr(T < t) = {res}0.9342         {txt}Pr(|T| > |t|) = {res}0.1316          {txt}Pr(T > t) = {res}0.0658
{txt}
{com}. ttest Confusion if OE==1 | DB==1, by(OE)

{txt}Two-sample t test with equal variances
{hline 9}{c TT}{hline 68}
   Group{col 10}{c |}{col 16}Obs{col 27}Mean{col 35}Std. Err.{col 47}Std. Dev.{col 59}[95% Conf. Interval]
{hline 9}{c +}{hline 68}
       0 {c |}{res}{col 12}     92{col 22}  1.51087{col 34} .0920834{col 46} .8832329{col 58} 1.327957{col 70} 1.693782
       {txt}1 {c |}{res}{col 12}     94{col 22} 1.542553{col 34} .1022117{col 46} .9909797{col 58} 1.339581{col 70} 1.745525
{txt}{hline 9}{c +}{hline 68}
combined {c |}{res}{col 12}    186{col 22} 1.526882{col 34} .0686918{col 46} .9368307{col 58} 1.391362{col 70} 1.662402
{txt}{hline 9}{c +}{hline 68}
    diff {c |}{res}{col 22}-.0316836{col 34} .1377445{col 58}-.3034453{col 70} .2400781
{txt}{hline 9}{c BT}{hline 68}
    diff = mean({res}0{txt}) - mean({res}1{txt})                                      t = {res} -0.2300
{txt}Ho: diff = 0                                     degrees of freedom = {res}     184

    {txt}Ha: diff < 0                 Ha: diff != 0                 Ha: diff > 0
 Pr(T < t) = {res}0.4092         {txt}Pr(|T| > |t|) = {res}0.8183          {txt}Pr(T > t) = {res}0.5908
{txt}
{com}. 
. ttest NeedInformation if PC==1 | SBC==1, by(PC)

{txt}Two-sample t test with equal variances
{hline 9}{c TT}{hline 68}
   Group{col 10}{c |}{col 16}Obs{col 27}Mean{col 35}Std. Err.{col 47}Std. Dev.{col 59}[95% Conf. Interval]
{hline 9}{c +}{hline 68}
       0 {c |}{res}{col 12}    130{col 22} 1.892308{col 34} .0984351{col 46} 1.122333{col 58} 1.697551{col 70} 2.087064
       {txt}1 {c |}{res}{col 12}     94{col 22} 2.095745{col 34}  .135345{col 46} 1.312218{col 58} 1.826976{col 70} 2.364513
{txt}{hline 9}{c +}{hline 68}
combined {c |}{res}{col 12}    224{col 22} 1.977679{col 34} .0806475{col 46} 1.207021{col 58}  1.81875{col 70} 2.136607
{txt}{hline 9}{c +}{hline 68}
    diff {c |}{res}{col 22} -.203437{col 34} .1632167{col 58}-.5250894{col 70} .1182154
{txt}{hline 9}{c BT}{hline 68}
    diff = mean({res}0{txt}) - mean({res}1{txt})                                      t = {res} -1.2464
{txt}Ho: diff = 0                                     degrees of freedom = {res}     222

    {txt}Ha: diff < 0                 Ha: diff != 0                 Ha: diff > 0
 Pr(T < t) = {res}0.1070         {txt}Pr(|T| > |t|) = {res}0.2139          {txt}Pr(T > t) = {res}0.8930
{txt}
{com}. ttest NeedInformation if PC==1 | OE==1, by(PC)

{txt}Two-sample t test with equal variances
{hline 9}{c TT}{hline 68}
   Group{col 10}{c |}{col 16}Obs{col 27}Mean{col 35}Std. Err.{col 47}Std. Dev.{col 59}[95% Conf. Interval]
{hline 9}{c +}{hline 68}
       0 {c |}{res}{col 12}     94{col 22} 1.957447{col 34} .1190165{col 46} 1.153908{col 58} 1.721104{col 70}  2.19379
       {txt}1 {c |}{res}{col 12}     94{col 22} 2.095745{col 34}  .135345{col 46} 1.312218{col 58} 1.826976{col 70} 2.364513
{txt}{hline 9}{c +}{hline 68}
combined {c |}{res}{col 12}    188{col 22} 2.026596{col 34} .0900163{col 46} 1.234242{col 58} 1.849018{col 70} 2.204174
{txt}{hline 9}{c +}{hline 68}
    diff {c |}{res}{col 22}-.1382979{col 34} .1802309{col 58}-.4938575{col 70} .2172618
{txt}{hline 9}{c BT}{hline 68}
    diff = mean({res}0{txt}) - mean({res}1{txt})                                      t = {res} -0.7673
{txt}Ho: diff = 0                                     degrees of freedom = {res}     186

    {txt}Ha: diff < 0                 Ha: diff != 0                 Ha: diff > 0
 Pr(T < t) = {res}0.2219         {txt}Pr(|T| > |t|) = {res}0.4439          {txt}Pr(T > t) = {res}0.7781
{txt}
{com}. ttest NeedInformation if PC==1 | DB==1, by(PC)

{txt}Two-sample t test with equal variances
{hline 9}{c TT}{hline 68}
   Group{col 10}{c |}{col 16}Obs{col 27}Mean{col 35}Std. Err.{col 47}Std. Dev.{col 59}[95% Conf. Interval]
{hline 9}{c +}{hline 68}
       0 {c |}{res}{col 12}     92{col 22} 1.771739{col 34} .0928696{col 46}  .890774{col 58} 1.587265{col 70} 1.956213
       {txt}1 {c |}{res}{col 12}     94{col 22} 2.095745{col 34}  .135345{col 46} 1.312218{col 58} 1.826976{col 70} 2.364513
{txt}{hline 9}{c +}{hline 68}
combined {c |}{res}{col 12}    186{col 22} 1.935484{col 34} .0830307{col 46} 1.132388{col 58} 1.771675{col 70} 2.099293
{txt}{hline 9}{c +}{hline 68}
    diff {c |}{res}{col 22}-.3240056{col 34} .1647996{col 58}-.6491454{col 70} .0011343
{txt}{hline 9}{c BT}{hline 68}
    diff = mean({res}0{txt}) - mean({res}1{txt})                                      t = {res} -1.9661
{txt}Ho: diff = 0                                     degrees of freedom = {res}     184

    {txt}Ha: diff < 0                 Ha: diff != 0                 Ha: diff > 0
 Pr(T < t) = {res}0.0254         {txt}Pr(|T| > |t|) = {res}0.0508          {txt}Pr(T > t) = {res}0.9746
{txt}
{com}. ttest NeedInformation if SBC==1 | OE==1, by(SBC)

{txt}Two-sample t test with equal variances
{hline 9}{c TT}{hline 68}
   Group{col 10}{c |}{col 16}Obs{col 27}Mean{col 35}Std. Err.{col 47}Std. Dev.{col 59}[95% Conf. Interval]
{hline 9}{c +}{hline 68}
       0 {c |}{res}{col 12}     94{col 22} 1.957447{col 34} .1190165{col 46} 1.153908{col 58} 1.721104{col 70}  2.19379
       {txt}1 {c |}{res}{col 12}    130{col 22} 1.892308{col 34} .0984351{col 46} 1.122333{col 58} 1.697551{col 70} 2.087064
{txt}{hline 9}{c +}{hline 68}
combined {c |}{res}{col 12}    224{col 22} 1.919643{col 34} .0757402{col 46} 1.133576{col 58} 1.770385{col 70} 2.068901
{txt}{hline 9}{c +}{hline 68}
    diff {c |}{res}{col 22} .0651391{col 34} .1537586{col 58} -.237874{col 70} .3681523
{txt}{hline 9}{c BT}{hline 68}
    diff = mean({res}0{txt}) - mean({res}1{txt})                                      t = {res}  0.4236
{txt}Ho: diff = 0                                     degrees of freedom = {res}     222

    {txt}Ha: diff < 0                 Ha: diff != 0                 Ha: diff > 0
 Pr(T < t) = {res}0.6639         {txt}Pr(|T| > |t|) = {res}0.6722          {txt}Pr(T > t) = {res}0.3361
{txt}
{com}. ttest NeedInformation if SBC==1 | DB==1, by(SBC)

{txt}Two-sample t test with equal variances
{hline 9}{c TT}{hline 68}
   Group{col 10}{c |}{col 16}Obs{col 27}Mean{col 35}Std. Err.{col 47}Std. Dev.{col 59}[95% Conf. Interval]
{hline 9}{c +}{hline 68}
       0 {c |}{res}{col 12}     92{col 22} 1.771739{col 34} .0928696{col 46}  .890774{col 58} 1.587265{col 70} 1.956213
       {txt}1 {c |}{res}{col 12}    130{col 22} 1.892308{col 34} .0984351{col 46} 1.122333{col 58} 1.697551{col 70} 2.087064
{txt}{hline 9}{c +}{hline 68}
combined {c |}{res}{col 12}    222{col 22} 1.842342{col 34} .0692797{col 46} 1.032245{col 58} 1.705809{col 70} 1.978876
{txt}{hline 9}{c +}{hline 68}
    diff {c |}{res}{col 22}-.1205686{col 34} .1407197{col 58}-.3978998{col 70} .1567627
{txt}{hline 9}{c BT}{hline 68}
    diff = mean({res}0{txt}) - mean({res}1{txt})                                      t = {res} -0.8568
{txt}Ho: diff = 0                                     degrees of freedom = {res}     220

    {txt}Ha: diff < 0                 Ha: diff != 0                 Ha: diff > 0
 Pr(T < t) = {res}0.1962         {txt}Pr(|T| > |t|) = {res}0.3925          {txt}Pr(T > t) = {res}0.8038
{txt}
{com}. ttest NeedInformation if OE==1 | DB==1, by(OE)

{txt}Two-sample t test with equal variances
{hline 9}{c TT}{hline 68}
   Group{col 10}{c |}{col 16}Obs{col 27}Mean{col 35}Std. Err.{col 47}Std. Dev.{col 59}[95% Conf. Interval]
{hline 9}{c +}{hline 68}
       0 {c |}{res}{col 12}     92{col 22} 1.771739{col 34} .0928696{col 46}  .890774{col 58} 1.587265{col 70} 1.956213
       {txt}1 {c |}{res}{col 12}     94{col 22} 1.957447{col 34} .1190165{col 46} 1.153908{col 58} 1.721104{col 70}  2.19379
{txt}{hline 9}{c +}{hline 68}
combined {c |}{res}{col 12}    186{col 22} 1.865591{col 34}  .075787{col 46} 1.033597{col 58} 1.716073{col 70} 2.015109
{txt}{hline 9}{c +}{hline 68}
    diff {c |}{res}{col 22}-.1857077{col 34} .1513763{col 58}-.4843642{col 70} .1129488
{txt}{hline 9}{c BT}{hline 68}
    diff = mean({res}0{txt}) - mean({res}1{txt})                                      t = {res} -1.2268
{txt}Ho: diff = 0                                     degrees of freedom = {res}     184

    {txt}Ha: diff < 0                 Ha: diff != 0                 Ha: diff > 0
 Pr(T < t) = {res}0.1107         {txt}Pr(|T| > |t|) = {res}0.2215          {txt}Pr(T > t) = {res}0.8893
{txt}
{com}. 
. ttest Certainty if PC==1 | SBC==1, by(PC)

{txt}Two-sample t test with equal variances
{hline 9}{c TT}{hline 68}
   Group{col 10}{c |}{col 16}Obs{col 27}Mean{col 35}Std. Err.{col 47}Std. Dev.{col 59}[95% Conf. Interval]
{hline 9}{c +}{hline 68}
       0 {c |}{res}{col 12}    130{col 22} 4.076923{col 34}  .086415{col 46} .9852823{col 58} 3.905949{col 70} 4.247897
       {txt}1 {c |}{res}{col 12}     94{col 22} 4.021277{col 34} .1171408{col 46} 1.135722{col 58} 3.788658{col 70} 4.253895
{txt}{hline 9}{c +}{hline 68}
combined {c |}{res}{col 12}    224{col 22} 4.053571{col 34} .0700847{col 46} 1.048931{col 58} 3.915458{col 70} 4.191684
{txt}{hline 9}{c +}{hline 68}
    diff {c |}{res}{col 22} .0556465{col 34} .1422859{col 58}-.2247573{col 70} .3360503
{txt}{hline 9}{c BT}{hline 68}
    diff = mean({res}0{txt}) - mean({res}1{txt})                                      t = {res}  0.3911
{txt}Ho: diff = 0                                     degrees of freedom = {res}     222

    {txt}Ha: diff < 0                 Ha: diff != 0                 Ha: diff > 0
 Pr(T < t) = {res}0.6519         {txt}Pr(|T| > |t|) = {res}0.6961          {txt}Pr(T > t) = {res}0.3481
{txt}
{com}. ttest Certainty if PC==1 | OE==1, by(PC)

{txt}Two-sample t test with equal variances
{hline 9}{c TT}{hline 68}
   Group{col 10}{c |}{col 16}Obs{col 27}Mean{col 35}Std. Err.{col 47}Std. Dev.{col 59}[95% Conf. Interval]
{hline 9}{c +}{hline 68}
       0 {c |}{res}{col 12}     94{col 22} 3.776596{col 34} .1163329{col 46} 1.127889{col 58} 3.545582{col 70}  4.00761
       {txt}1 {c |}{res}{col 12}     94{col 22} 4.021277{col 34} .1171408{col 46} 1.135722{col 58} 3.788658{col 70} 4.253895
{txt}{hline 9}{c +}{hline 68}
combined {c |}{res}{col 12}    188{col 22} 3.898936{col 34} .0828096{col 46} 1.135428{col 58} 3.735575{col 70} 4.062297
{txt}{hline 9}{c +}{hline 68}
    diff {c |}{res}{col 22}-.2446809{col 34} .1650918{col 58} -.570374{col 70} .0810123
{txt}{hline 9}{c BT}{hline 68}
    diff = mean({res}0{txt}) - mean({res}1{txt})                                      t = {res} -1.4821
{txt}Ho: diff = 0                                     degrees of freedom = {res}     186

    {txt}Ha: diff < 0                 Ha: diff != 0                 Ha: diff > 0
 Pr(T < t) = {res}0.0700         {txt}Pr(|T| > |t|) = {res}0.1400          {txt}Pr(T > t) = {res}0.9300
{txt}
{com}. ttest Certainty if PC==1 | DB==1, by(PC)

{txt}Two-sample t test with equal variances
{hline 9}{c TT}{hline 68}
   Group{col 10}{c |}{col 16}Obs{col 27}Mean{col 35}Std. Err.{col 47}Std. Dev.{col 59}[95% Conf. Interval]
{hline 9}{c +}{hline 68}
       0 {c |}{res}{col 12}     92{col 22} 4.141304{col 34} .0947518{col 46} .9088275{col 58} 3.953091{col 70} 4.329517
       {txt}1 {c |}{res}{col 12}     94{col 22} 4.021277{col 34} .1171408{col 46} 1.135722{col 58} 3.788658{col 70} 4.253895
{txt}{hline 9}{c +}{hline 68}
combined {c |}{res}{col 12}    186{col 22} 4.080645{col 34} .0754316{col 46}  1.02875{col 58} 3.931828{col 70} 4.229462
{txt}{hline 9}{c +}{hline 68}
    diff {c |}{res}{col 22} .1200278{col 34} .1510223{col 58}-.1779303{col 70} .4179858
{txt}{hline 9}{c BT}{hline 68}
    diff = mean({res}0{txt}) - mean({res}1{txt})                                      t = {res}  0.7948
{txt}Ho: diff = 0                                     degrees of freedom = {res}     184

    {txt}Ha: diff < 0                 Ha: diff != 0                 Ha: diff > 0
 Pr(T < t) = {res}0.7861         {txt}Pr(|T| > |t|) = {res}0.4278          {txt}Pr(T > t) = {res}0.2139
{txt}
{com}. ttest Certainty if SBC==1 | OE==1, by(SBC)

{txt}Two-sample t test with equal variances
{hline 9}{c TT}{hline 68}
   Group{col 10}{c |}{col 16}Obs{col 27}Mean{col 35}Std. Err.{col 47}Std. Dev.{col 59}[95% Conf. Interval]
{hline 9}{c +}{hline 68}
       0 {c |}{res}{col 12}     94{col 22} 3.776596{col 34} .1163329{col 46} 1.127889{col 58} 3.545582{col 70}  4.00761
       {txt}1 {c |}{res}{col 12}    130{col 22} 4.076923{col 34}  .086415{col 46} .9852823{col 58} 3.905949{col 70} 4.247897
{txt}{hline 9}{c +}{hline 68}
combined {c |}{res}{col 12}    224{col 22} 3.950893{col 34} .0705264{col 46} 1.055542{col 58} 3.811909{col 70} 4.089876
{txt}{hline 9}{c +}{hline 68}
    diff {c |}{res}{col 22}-.3003273{col 34} .1418066{col 58}-.5797866{col 70} -.020868
{txt}{hline 9}{c BT}{hline 68}
    diff = mean({res}0{txt}) - mean({res}1{txt})                                      t = {res} -2.1179
{txt}Ho: diff = 0                                     degrees of freedom = {res}     222

    {txt}Ha: diff < 0                 Ha: diff != 0                 Ha: diff > 0
 Pr(T < t) = {res}0.0176         {txt}Pr(|T| > |t|) = {res}0.0353          {txt}Pr(T > t) = {res}0.9824
{txt}
{com}. ttest Certainty if SBC==1 | DB==1, by(SBC)

{txt}Two-sample t test with equal variances
{hline 9}{c TT}{hline 68}
   Group{col 10}{c |}{col 16}Obs{col 27}Mean{col 35}Std. Err.{col 47}Std. Dev.{col 59}[95% Conf. Interval]
{hline 9}{c +}{hline 68}
       0 {c |}{res}{col 12}     92{col 22} 4.141304{col 34} .0947518{col 46} .9088275{col 58} 3.953091{col 70} 4.329517
       {txt}1 {c |}{res}{col 12}    130{col 22} 4.076923{col 34}  .086415{col 46} .9852823{col 58} 3.905949{col 70} 4.247897
{txt}{hline 9}{c +}{hline 68}
combined {c |}{res}{col 12}    222{col 22} 4.103604{col 34} .0639457{col 46} .9527695{col 58} 3.977582{col 70} 4.229625
{txt}{hline 9}{c +}{hline 68}
    diff {c |}{res}{col 22} .0643813{col 34} .1300294{col 58}-.1918815{col 70}  .320644
{txt}{hline 9}{c BT}{hline 68}
    diff = mean({res}0{txt}) - mean({res}1{txt})                                      t = {res}  0.4951
{txt}Ho: diff = 0                                     degrees of freedom = {res}     220

    {txt}Ha: diff < 0                 Ha: diff != 0                 Ha: diff > 0
 Pr(T < t) = {res}0.6895         {txt}Pr(|T| > |t|) = {res}0.6210          {txt}Pr(T > t) = {res}0.3105
{txt}
{com}. ttest Certainty if OE==1 | DB==1, by(OE)

{txt}Two-sample t test with equal variances
{hline 9}{c TT}{hline 68}
   Group{col 10}{c |}{col 16}Obs{col 27}Mean{col 35}Std. Err.{col 47}Std. Dev.{col 59}[95% Conf. Interval]
{hline 9}{c +}{hline 68}
       0 {c |}{res}{col 12}     92{col 22} 4.141304{col 34} .0947518{col 46} .9088275{col 58} 3.953091{col 70} 4.329517
       {txt}1 {c |}{res}{col 12}     94{col 22} 3.776596{col 34} .1163329{col 46} 1.127889{col 58} 3.545582{col 70}  4.00761
{txt}{hline 9}{c +}{hline 68}
combined {c |}{res}{col 12}    186{col 22} 3.956989{col 34} .0761726{col 46} 1.038856{col 58} 3.806711{col 70} 4.107268
{txt}{hline 9}{c +}{hline 68}
    diff {c |}{res}{col 22} .3647086{col 34} .1503828{col 58} .0680122{col 70}  .661405
{txt}{hline 9}{c BT}{hline 68}
    diff = mean({res}0{txt}) - mean({res}1{txt})                                      t = {res}  2.4252
{txt}Ho: diff = 0                                     degrees of freedom = {res}     184

    {txt}Ha: diff < 0                 Ha: diff != 0                 Ha: diff > 0
 Pr(T < t) = {res}0.9919         {txt}Pr(|T| > |t|) = {res}0.0163          {txt}Pr(T > t) = {res}0.0081
{txt}
{com}. 
. 
. ***Table 2: Empirical Survival Functions – Percentage of “Yes” Votes by Cost 
. tab CostSBC ChoiceSBC if SBC==1, row nofreq

   {txt}Cost to {c |}
participan {c |}  =1 for yes vote in
  t in SBC {c |}     SBC treatment
 treatment {c |}         0          1 {c |}     Total
{hline 11}{c +}{hline 22}{c +}{hline 10}
         1 {c |}{res}     20.83      79.17 {txt}{c |}{res}    100.00 
{txt}         2 {c |}{res}     27.27      72.73 {txt}{c |}{res}    100.00 
{txt}         3 {c |}{res}     38.10      61.90 {txt}{c |}{res}    100.00 
{txt}         4 {c |}{res}     50.00      50.00 {txt}{c |}{res}    100.00 
{txt}         5 {c |}{res}     66.67      33.33 {txt}{c |}{res}    100.00 
{txt}         6 {c |}{res}     75.00      25.00 {txt}{c |}{res}    100.00 
{txt}{hline 11}{c +}{hline 22}{c +}{hline 10}
     Total {c |}{res}     45.38      54.62 {txt}{c |}{res}    100.00 
{txt}
{com}. sum ChoiceDB_1-ChoiceDB_6 if DB==1

{txt}    Variable {c |}        Obs        Mean    Std. Dev.       Min        Max
{hline 13}{c +}{hline 57}
{space 2}ChoiceDB_1 {c |}{res}         71    .8732394    .3350726          0          1
{txt}{space 2}ChoiceDB_2 {c |}{res}         76         .75    .4358899          0          1
{txt}{space 2}ChoiceDB_3 {c |}{res}         76    .5657895    .4989463          0          1
{txt}{space 2}ChoiceDB_4 {c |}{res}         75    .5066667    .5033223          0          1
{txt}{space 2}ChoiceDB_5 {c |}{res}         72    .3194444    .4695334          0          1
{txt}{hline 13}{c +}{hline 57}
{space 2}ChoiceDB_6 {c |}{res}         73    .2054795    .4068478          0          1
{txt}
{com}. sum ChoicePC0-ChoicePC10 if PC==1

{txt}    Variable {c |}        Obs        Mean    Std. Dev.       Min        Max
{hline 13}{c +}{hline 57}
{space 3}ChoicePC0 {c |}{res}         94    .8297872    .3778347          0          1
{txt}{space 3}ChoicePC1 {c |}{res}         94    .7446809    .4383785          0          1
{txt}{space 3}ChoicePC2 {c |}{res}         94    .6702128    .4726566          0          1
{txt}{space 3}ChoicePC3 {c |}{res}         94    .5638298    .4985681          0          1
{txt}{space 3}ChoicePC4 {c |}{res}         94    .4148936    .4953455          0          1
{txt}{hline 13}{c +}{hline 57}
{space 3}ChoicePC5 {c |}{res}         94    .3617021    .4830696          0          1
{txt}{space 3}ChoicePC6 {c |}{res}         94    .2021277    .4037402          0          1
{txt}{space 3}ChoicePC7 {c |}{res}         94    .1702128    .3778347          0          1
{txt}{space 3}ChoicePC8 {c |}{res}         94    .1276596    .3354997          0          1
{txt}{space 3}ChoicePC9 {c |}{res}         94    .1276596    .3354997          0          1
{txt}{hline 13}{c +}{hline 57}
{space 2}ChoicePC10 {c |}{res}         94    .1276596    .3354997          0          1
{txt}
{com}. sum OE1-OE10 if OE==1

{txt}    Variable {c |}        Obs        Mean    Std. Dev.       Min        Max
{hline 13}{c +}{hline 57}
{space 9}OE1 {c |}{res}         94    .8404255    .3681746          0          1
{txt}{space 9}OE2 {c |}{res}         94     .712766    .4548978          0          1
{txt}{space 9}OE3 {c |}{res}         94    .5957447    .4933787          0          1
{txt}{space 9}OE4 {c |}{res}         94    .4255319    .4970745          0          1
{txt}{space 9}OE5 {c |}{res}         94    .3510638    .4798621          0          1
{txt}{hline 13}{c +}{hline 57}
{space 9}OE6 {c |}{res}         94    .1702128    .3778347          0          1
{txt}{space 9}OE7 {c |}{res}         94    .1382979    .3470634          0          1
{txt}{space 9}OE8 {c |}{res}         94    .0957447    .2958185          0          1
{txt}{space 9}OE9 {c |}{res}         94    .0851064    .2805361          0          1
{txt}{space 8}OE10 {c |}{res}         94    .0851064    .2805361          0          1
{txt}
{com}. 
. 
. ***Table 3, Model I: interval regression, equal variances, no controls
. intreg LB UB DB PC OE

{txt}Fitting constant-only model:
{res}
{txt}Iteration 0:{space 3}log likelihood = {res:-709.64996}  
Iteration 1:{space 3}log likelihood = {res: -670.6813}  
Iteration 2:{space 3}log likelihood = {res:-669.21765}  
Iteration 3:{space 3}log likelihood = {res: -669.2136}  
Iteration 4:{space 3}log likelihood = {res: -669.2136}  
{res}
{txt}Fitting full model:
{res}
{txt}Iteration 0:{space 3}log likelihood = {res: -710.1844}  
Iteration 1:{space 3}log likelihood = {res:-670.61776}  
Iteration 2:{space 3}log likelihood = {res:-669.13776}  
Iteration 3:{space 3}log likelihood = {res:-669.13359}  
Iteration 4:{space 3}log likelihood = {res:-669.13359}  
{res}
{txt}Interval regression{col 49}Number of obs{col 67}= {res}       410
{txt}{col 49}   Uncensored    {col 67}= {res}        82
{txt}{col 49}   Left-censored {col 67}= {res}       111
{txt}{col 49}   Right-censored{col 67}= {res}       116
{txt}{col 49}   Interval-cens.{col 67}= {res}       101

{txt}{col 49}LR chi2({res}3{txt}){col 67}= {res}      0.16
{txt}Log likelihood = {res}-669.13359{txt}{col 49}Prob > chi2{col 67}= {res}    0.9838

{txt}{hline 13}{c TT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{col 14}{c |}      Coef.{col 26}   Std. Err.{col 38}      z{col 46}   P>|z|{col 54}     [95% Con{col 67}f. Interval]
{hline 13}{c +}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{space 10}DB {c |}{col 14}{res}{space 2}-.0971702{col 26}{space 2} .6822575{col 37}{space 1}   -0.14{col 46}{space 3}0.887{col 54}{space 4} -1.43437{col 67}{space 3}  1.24003
{txt}{space 10}PC {c |}{col 14}{res}{space 2}-.1281698{col 26}{space 2} .6464935{col 37}{space 1}   -0.20{col 46}{space 3}0.843{col 54}{space 4}-1.395274{col 67}{space 3} 1.138934
{txt}{space 10}OE {c |}{col 14}{res}{space 2}-.2537564{col 26}{space 2} .6452052{col 37}{space 1}   -0.39{col 46}{space 3}0.694{col 54}{space 4}-1.518335{col 67}{space 3} 1.010823
{txt}{space 7}_cons {c |}{col 14}{res}{space 2} 3.939168{col 26}{space 2} .4754371{col 37}{space 1}    8.29{col 46}{space 3}0.000{col 54}{space 4} 3.007328{col 67}{space 3} 4.871008
{txt}{hline 13}{c +}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
    /lnsigma {c |}{col 14}{res}{space 2} 1.423984{col 26}{space 2} .0544106{col 37}{space 1}   26.17{col 46}{space 3}0.000{col 54}{space 4} 1.317341{col 67}{space 3} 1.530627
{txt}{hline 13}{c +}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
       sigma {c |}{col 14}{res}{space 2} 4.153636{col 26}{space 2} .2260017{col 54}{space 4} 3.733482{col 67}{space 3} 4.621072
{txt}{hline 13}{c BT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}

{com}. // Tests of treatment effects
. test OE=DB

{p 0 7}{space 1}{text:( 1)}{space 1}{space 1}{res}- [model]DB + [model]OE = 0{p_end}

{txt}{col 12}chi2(  1) ={res}    0.06
{txt}{col 10}Prob > chi2 =  {res}  0.8112
{txt}
{com}. test OE=PC

{p 0 7}{space 1}{text:( 1)}{space 1}{space 1}{res}- [model]PC + [model]OE = 0{p_end}

{txt}{col 12}chi2(  1) ={res}    0.04
{txt}{col 10}Prob > chi2 =  {res}  0.8388
{txt}
{com}. test DB=PC

{p 0 7}{space 1}{text:( 1)}{space 1} {res}[model]DB - [model]PC = 0{p_end}

{txt}{col 12}chi2(  1) ={res}    0.00
{txt}{col 10}Prob > chi2 =  {res}  0.9624
{txt}
{com}. test OE=DB=PC=0

{p 0 7}{space 1}{text:( 1)}{space 1}{space 1}{res}- [model]DB + [model]OE = 0{p_end}
{p 0 7}{space 1}{text:( 2)}{space 1}{space 1}{res}- [model]PC + [model]OE = 0{p_end}
{p 0 7}{space 1}{text:( 3)}{space 1} [model]OE = 0{p_end}

{txt}{col 12}chi2(  3) ={res}    0.16
{txt}{col 10}Prob > chi2 =  {res}  0.9838
{txt}
{com}. // Treatment-specific WTP estimates
. lincom _cons + DB // WTP in DB treatment

{p 0 7}{space 1}{text:( 1)}{space 1} {res}[model]DB + [model]_cons = 0{p_end}

{txt}{hline 13}{c TT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{col 14}{c |}      Coef.{col 26}   Std. Err.{col 38}      z{col 46}   P>|z|{col 54}     [95% Con{col 67}f. Interval]
{hline 13}{c +}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{space 9}(1) {c |}{col 14}{res}{space 2} 3.841998{col 26}{space 2} .4898425{col 37}{space 1}    7.84{col 46}{space 3}0.000{col 54}{space 4} 2.881924{col 67}{space 3} 4.802071
{txt}{hline 13}{c BT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}

{com}. lincom _cons + PC // WTP in PC treatment

{p 0 7}{space 1}{text:( 1)}{space 1} {res}[model]PC + [model]_cons = 0{p_end}

{txt}{hline 13}{c TT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{col 14}{c |}      Coef.{col 26}   Std. Err.{col 38}      z{col 46}   P>|z|{col 54}     [95% Con{col 67}f. Interval]
{hline 13}{c +}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{space 9}(1) {c |}{col 14}{res}{space 2} 3.810998{col 26}{space 2} .4380654{col 37}{space 1}    8.70{col 46}{space 3}0.000{col 54}{space 4} 2.952406{col 67}{space 3} 4.669591
{txt}{hline 13}{c BT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}

{com}. lincom _cons + OE // WTP in OE treatment

{p 0 7}{space 1}{text:( 1)}{space 1} {res}[model]OE + [model]_cons = 0{p_end}

{txt}{hline 13}{c TT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{col 14}{c |}      Coef.{col 26}   Std. Err.{col 38}      z{col 46}   P>|z|{col 54}     [95% Con{col 67}f. Interval]
{hline 13}{c +}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{space 9}(1) {c |}{col 14}{res}{space 2} 3.685412{col 26}{space 2} .4349049{col 37}{space 1}    8.47{col 46}{space 3}0.000{col 54}{space 4} 2.833014{col 67}{space 3}  4.53781
{txt}{hline 13}{c BT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}

{com}. 
. 
. ***Table 3, Model II: interval regression, allow for different variances, no controls
. intreg LB UB DB PC OE, het(DB PC OE)

{txt}Fitting full model:
{res}
{txt}Iteration 0:{space 3}log likelihood = {res:-1111.4953}  
Iteration 1:{space 3}log likelihood = {res:-676.77597}  
Iteration 2:{space 3}log likelihood = {res: -670.1773}  
Iteration 3:{space 3}log likelihood = {res:-667.97001}  
Iteration 4:{space 3}log likelihood = {res:-667.91673}  
Iteration 5:{space 3}log likelihood = {res:-667.91667}  
{res}
{txt}Interval regression{col 49}Number of obs{col 67}= {res}       410
{txt}{col 49}   Uncensored    {col 67}= {res}        82
{txt}{col 49}   Left-censored {col 67}= {res}       111
{txt}{col 49}   Right-censored{col 67}= {res}       116
{txt}{col 49}   Interval-cens.{col 67}= {res}       101

{txt}{col 49}Wald chi2({res}3{txt}){col 67}= {res}      0.11
{txt}Log likelihood = {res}-667.91667{txt}{col 49}Prob > chi2{col 67}= {res}    0.9905

{txt}{hline 13}{c TT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{col 14}{c |}      Coef.{col 26}   Std. Err.{col 38}      z{col 46}   P>|z|{col 54}     [95% Con{col 67}f. Interval]
{hline 13}{c +}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{res}model        {txt}{c |}
{space 10}DB {c |}{col 14}{res}{space 2} .0042384{col 26}{space 2} .6185569{col 37}{space 1}    0.01{col 46}{space 3}0.995{col 54}{space 4}-1.208111{col 67}{space 3} 1.216588
{txt}{space 10}PC {c |}{col 14}{res}{space 2}-.0247686{col 26}{space 2}   .55926{col 37}{space 1}   -0.04{col 46}{space 3}0.965{col 54}{space 4}-1.120898{col 67}{space 3} 1.071361
{txt}{space 10}OE {c |}{col 14}{res}{space 2}-.1810083{col 26}{space 2} .6044877{col 37}{space 1}   -0.30{col 46}{space 3}0.765{col 54}{space 4}-1.365783{col 67}{space 3} 1.003766
{txt}{space 7}_cons {c |}{col 14}{res}{space 2}  3.83619{col 26}{space 2} .3820783{col 37}{space 1}   10.04{col 46}{space 3}0.000{col 54}{space 4} 3.087331{col 67}{space 3}  4.58505
{txt}{hline 13}{c +}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{res}lnsigma      {txt}{c |}
{space 10}DB {c |}{col 14}{res}{space 2} .2446655{col 26}{space 2} .2777594{col 37}{space 1}    0.88{col 46}{space 3}0.378{col 54}{space 4}-.2997329{col 67}{space 3} .7890639
{txt}{space 10}PC {c |}{col 14}{res}{space 2} .1837216{col 26}{space 2} .2429886{col 37}{space 1}    0.76{col 46}{space 3}0.450{col 54}{space 4}-.2925273{col 67}{space 3} .6599705
{txt}{space 10}OE {c |}{col 14}{res}{space 2} .3253035{col 26}{space 2} .2399646{col 37}{space 1}    1.36{col 46}{space 3}0.175{col 54}{space 4}-.1450184{col 67}{space 3} .7956254
{txt}{space 7}_cons {c |}{col 14}{res}{space 2} 1.170815{col 26}{space 2} .2261966{col 37}{space 1}    5.18{col 46}{space 3}0.000{col 54}{space 4} .7274776{col 67}{space 3} 1.614152
{txt}{hline 13}{c BT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}

{com}. // Tests of treatment effects
. test OE=DB=PC=0

{p 0 7}{space 1}{text:( 1)}{space 1}{space 1}{res}- [model]DB + [model]OE = 0{p_end}
{p 0 7}{space 1}{text:( 2)}{space 1}{space 1}{res}- [model]PC + [model]OE = 0{p_end}
{p 0 7}{space 1}{text:( 3)}{space 1} [model]OE = 0{p_end}

{txt}{col 12}chi2(  3) ={res}    0.11
{txt}{col 10}Prob > chi2 =  {res}  0.9905
{txt}
{com}. test OE=DB

{p 0 7}{space 1}{text:( 1)}{space 1}{space 1}{res}- [model]DB + [model]OE = 0{p_end}

{txt}{col 12}chi2(  1) ={res}    0.08
{txt}{col 10}Prob > chi2 =  {res}  0.7838
{txt}
{com}. test OE=PC

{p 0 7}{space 1}{text:( 1)}{space 1}{space 1}{res}- [model]PC + [model]OE = 0{p_end}

{txt}{col 12}chi2(  1) ={res}    0.06
{txt}{col 10}Prob > chi2 =  {res}  0.8015
{txt}
{com}. test DB=PC

{p 0 7}{space 1}{text:( 1)}{space 1} {res}[model]DB - [model]PC = 0{p_end}

{txt}{col 12}chi2(  1) ={res}    0.00
{txt}{col 10}Prob > chi2 =  {res}  0.9636
{txt}
{com}. // Treatment-specific WTP estimates
. lincom _cons + DB // WTP in DB treatment

{p 0 7}{space 1}{text:( 1)}{space 1} {res}[model]DB + [model]_cons = 0{p_end}

{txt}{hline 13}{c TT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{col 14}{c |}      Coef.{col 26}   Std. Err.{col 38}      z{col 46}   P>|z|{col 54}     [95% Con{col 67}f. Interval]
{hline 13}{c +}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{space 9}(1) {c |}{col 14}{res}{space 2} 3.840429{col 26}{space 2} .4864451{col 37}{space 1}    7.89{col 46}{space 3}0.000{col 54}{space 4} 2.887014{col 67}{space 3} 4.793843
{txt}{hline 13}{c BT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}

{com}. lincom _cons + PC // WTP in PC treatment

{p 0 7}{space 1}{text:( 1)}{space 1} {res}[model]PC + [model]_cons = 0{p_end}

{txt}{hline 13}{c TT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{col 14}{c |}      Coef.{col 26}   Std. Err.{col 38}      z{col 46}   P>|z|{col 54}     [95% Con{col 67}f. Interval]
{hline 13}{c +}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{space 9}(1) {c |}{col 14}{res}{space 2} 3.811422{col 26}{space 2} .4083968{col 37}{space 1}    9.33{col 46}{space 3}0.000{col 54}{space 4} 3.010979{col 67}{space 3} 4.611865
{txt}{hline 13}{c BT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}

{com}. lincom _cons + OE // WTP in OE treatment

{p 0 7}{space 1}{text:( 1)}{space 1} {res}[model]OE + [model]_cons = 0{p_end}

{txt}{hline 13}{c TT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{col 14}{c |}      Coef.{col 26}   Std. Err.{col 38}      z{col 46}   P>|z|{col 54}     [95% Con{col 67}f. Interval]
{hline 13}{c +}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{space 9}(1) {c |}{col 14}{res}{space 2} 3.655182{col 26}{space 2} .4684246{col 37}{space 1}    7.80{col 46}{space 3}0.000{col 54}{space 4} 2.737087{col 67}{space 3} 4.573277
{txt}{hline 13}{c BT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}

{com}. // convert ln(std dev) into std dev
. nlcom exp([lnsigma]_cons+[lnsigma]DB) - exp([lnsigma]_cons) // STD DEV of WTP for DB (relative to SBC)

       {txt}_nl_1:  {res}exp([lnsigma]_cons+[lnsigma]DB) - exp([lnsigma]_cons)

{txt}{hline 13}{c TT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{col 14}{c |}      Coef.{col 26}   Std. Err.{col 38}      z{col 46}   P>|z|{col 54}     [95% Con{col 67}f. Interval]
{hline 13}{c +}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{space 7}_nl_1 {c |}{col 14}{res}{space 2} .8938449{col 26}{space 2} .9862954{col 37}{space 1}    0.91{col 46}{space 3}0.365{col 54}{space 4}-1.039259{col 67}{space 3} 2.826948
{txt}{hline 13}{c BT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}

{com}. nlcom exp([lnsigma]_cons+[lnsigma]PC) - exp([lnsigma]_cons) // STD DEV of WTP for PC (relative to SBC)

       {txt}_nl_1:  {res}exp([lnsigma]_cons+[lnsigma]PC) - exp([lnsigma]_cons)

{txt}{hline 13}{c TT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{col 14}{c |}      Coef.{col 26}   Std. Err.{col 38}      z{col 46}   P>|z|{col 54}     [95% Con{col 67}f. Interval]
{hline 13}{c +}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{space 7}_nl_1 {c |}{col 14}{res}{space 2} .6503451{col 26}{space 2} .8064245{col 37}{space 1}    0.81{col 46}{space 3}0.420{col 54}{space 4}-.9302178{col 67}{space 3} 2.230908
{txt}{hline 13}{c BT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}

{com}. nlcom exp([lnsigma]_cons+[lnsigma]OE) - exp([lnsigma]_cons) // STD DEV of WTP for OE (relative to SBC)

       {txt}_nl_1:  {res}exp([lnsigma]_cons+[lnsigma]OE) - exp([lnsigma]_cons)

{txt}{hline 13}{c TT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{col 14}{c |}      Coef.{col 26}   Std. Err.{col 38}      z{col 46}   P>|z|{col 54}     [95% Con{col 67}f. Interval]
{hline 13}{c +}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{space 7}_nl_1 {c |}{col 14}{res}{space 2} 1.239707{col 26}{space 2} .8123639{col 37}{space 1}    1.53{col 46}{space 3}0.127{col 54}{space 4}-.3524968{col 67}{space 3} 2.831911
{txt}{hline 13}{c BT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}

{com}. nlcom exp([lnsigma]_cons) // STD DEV of WTP for SBC

       {txt}_nl_1:  {res}exp([lnsigma]_cons)

{txt}{hline 13}{c TT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{col 14}{c |}      Coef.{col 26}   Std. Err.{col 38}      z{col 46}   P>|z|{col 54}     [95% Con{col 67}f. Interval]
{hline 13}{c +}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{space 7}_nl_1 {c |}{col 14}{res}{space 2} 3.224619{col 26}{space 2} .7293976{col 37}{space 1}    4.42{col 46}{space 3}0.000{col 54}{space 4} 1.795026{col 67}{space 3} 4.654212
{txt}{hline 13}{c BT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}

{com}. 
. 
. ***Table 3, Model III: interval regression, allow for different variances, include controls
. intreg LB UB DB PC OE Age_demean Female_demean EarnedIncome_demean Employed_demean GPA_demean PriorExperiment_demean, het(DB PC OE)

{txt}Fitting full model:
{res}
{txt}Iteration 0:{space 3}log likelihood = {res:-1104.2875}  
Iteration 1:{space 3}log likelihood = {res:-667.72332}  
Iteration 2:{space 3}log likelihood = {res:-660.28625}  
Iteration 3:{space 3}log likelihood = {res:-657.84398}  
Iteration 4:{space 3}log likelihood = {res:-657.80713}  
Iteration 5:{space 3}log likelihood = {res:-657.80704}  
Iteration 6:{space 3}log likelihood = {res:-657.80704}  
{res}
{txt}Interval regression{col 49}Number of obs{col 67}= {res}       410
{txt}{col 49}   Uncensored    {col 67}= {res}        82
{txt}{col 49}   Left-censored {col 67}= {res}       111
{txt}{col 49}   Right-censored{col 67}= {res}       116
{txt}{col 49}   Interval-cens.{col 67}= {res}       101

{txt}{col 49}Wald chi2({res}9{txt}){col 67}= {res}     17.31
{txt}Log likelihood = {res}-657.80704{txt}{col 49}Prob > chi2{col 67}= {res}    0.0441

{txt}{hline 21}{c TT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{col 22}{c |}      Coef.{col 34}   Std. Err.{col 46}      z{col 54}   P>|z|{col 62}     [95% Con{col 75}f. Interval]
{hline 21}{c +}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{res}model                {txt}{c |}
{space 18}DB {c |}{col 22}{res}{space 2}-.0333471{col 34}{space 2} .6383358{col 45}{space 1}   -0.05{col 54}{space 3}0.958{col 62}{space 4}-1.284462{col 75}{space 3} 1.217768
{txt}{space 18}PC {c |}{col 22}{res}{space 2} .2001559{col 34}{space 2} .5626669{col 45}{space 1}    0.36{col 54}{space 3}0.722{col 62}{space 4}-.9026509{col 75}{space 3} 1.302963
{txt}{space 18}OE {c |}{col 22}{res}{space 2}-.1242325{col 34}{space 2} .6417725{col 45}{space 1}   -0.19{col 54}{space 3}0.847{col 62}{space 4}-1.382084{col 75}{space 3} 1.133619
{txt}{space 10}Age_demean {c |}{col 22}{res}{space 2} .3033824{col 34}{space 2} .1026476{col 45}{space 1}    2.96{col 54}{space 3}0.003{col 62}{space 4} .1021968{col 75}{space 3} .5045681
{txt}{space 7}Female_demean {c |}{col 22}{res}{space 2} 1.065452{col 34}{space 2} .4513605{col 45}{space 1}    2.36{col 54}{space 3}0.018{col 62}{space 4} .1808014{col 75}{space 3} 1.950102
{txt}{space 1}EarnedIncome_demean {c |}{col 22}{res}{space 2} -.060463{col 34}{space 2} .0625786{col 45}{space 1}   -0.97{col 54}{space 3}0.334{col 62}{space 4}-.1831147{col 75}{space 3} .0621887
{txt}{space 5}Employed_demean {c |}{col 22}{res}{space 2} .1832481{col 34}{space 2} .4417997{col 45}{space 1}    0.41{col 54}{space 3}0.678{col 62}{space 4}-.6826633{col 75}{space 3}  1.04916
{txt}{space 10}GPA_demean {c |}{col 22}{res}{space 2} .5710761{col 34}{space 2}  .433455{col 45}{space 1}    1.32{col 54}{space 3}0.188{col 62}{space 4}  -.27848{col 75}{space 3} 1.420632
{txt}PriorExperiment_de~n {c |}{col 22}{res}{space 2}-.8972803{col 34}{space 2} .4887299{col 45}{space 1}   -1.84{col 54}{space 3}0.066{col 62}{space 4}-1.855173{col 75}{space 3} .0606126
{txt}{space 15}_cons {c |}{col 22}{res}{space 2} 3.795464{col 34}{space 2} .4149579{col 45}{space 1}    9.15{col 54}{space 3}0.000{col 62}{space 4} 2.982161{col 75}{space 3} 4.608766
{txt}{hline 21}{c +}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{res}lnsigma              {txt}{c |}
{space 18}DB {c |}{col 22}{res}{space 2} .1620479{col 34}{space 2} .2869318{col 45}{space 1}    0.56{col 54}{space 3}0.572{col 62}{space 4} -.400328{col 75}{space 3} .7244239
{txt}{space 18}PC {c |}{col 22}{res}{space 2} .0515127{col 34}{space 2} .2586279{col 45}{space 1}    0.20{col 54}{space 3}0.842{col 62}{space 4}-.4553885{col 75}{space 3}  .558414
{txt}{space 18}OE {c |}{col 22}{res}{space 2} .2707522{col 34}{space 2} .2530839{col 45}{space 1}    1.07{col 54}{space 3}0.285{col 62}{space 4}-.2252832{col 75}{space 3} .7667877
{txt}{space 15}_cons {c |}{col 22}{res}{space 2} 1.228391{col 34}{space 2} .2406467{col 45}{space 1}    5.10{col 54}{space 3}0.000{col 62}{space 4} .7567321{col 75}{space 3}  1.70005
{txt}{hline 21}{c BT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}

{com}. // Tests of treatment effects
. test OE=DB=PC=0

{p 0 7}{space 1}{text:( 1)}{space 1}{space 1}{res}- [model]DB + [model]OE = 0{p_end}
{p 0 7}{space 1}{text:( 2)}{space 1}{space 1}{res}- [model]PC + [model]OE = 0{p_end}
{p 0 7}{space 1}{text:( 3)}{space 1} [model]OE = 0{p_end}

{txt}{col 12}chi2(  3) ={res}    0.33
{txt}{col 10}Prob > chi2 =  {res}  0.9552
{txt}
{com}. test OE=DB 

{p 0 7}{space 1}{text:( 1)}{space 1}{space 1}{res}- [model]DB + [model]OE = 0{p_end}

{txt}{col 12}chi2(  1) ={res}    0.02
{txt}{col 10}Prob > chi2 =  {res}  0.8937
{txt}
{com}. test OE=PC

{p 0 7}{space 1}{text:( 1)}{space 1}{space 1}{res}- [model]PC + [model]OE = 0{p_end}

{txt}{col 12}chi2(  1) ={res}    0.28
{txt}{col 10}Prob > chi2 =  {res}  0.5967
{txt}
{com}. test DB=PC

{p 0 7}{space 1}{text:( 1)}{space 1} {res}[model]DB - [model]PC = 0{p_end}

{txt}{col 12}chi2(  1) ={res}    0.14
{txt}{col 10}Prob > chi2 =  {res}  0.7052
{txt}
{com}. // Treatment-specific WTP estimates
. lincom _cons + DB // WTP in DB treatment

{p 0 7}{space 1}{text:( 1)}{space 1} {res}[model]DB + [model]_cons = 0{p_end}

{txt}{hline 13}{c TT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{col 14}{c |}      Coef.{col 26}   Std. Err.{col 38}      z{col 46}   P>|z|{col 54}     [95% Con{col 67}f. Interval]
{hline 13}{c +}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{space 9}(1) {c |}{col 14}{res}{space 2} 3.762117{col 26}{space 2} .4817122{col 37}{space 1}    7.81{col 46}{space 3}0.000{col 54}{space 4} 2.817978{col 67}{space 3} 4.706255
{txt}{hline 13}{c BT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}

{com}. lincom _cons + PC // WTP in PC treatment

{p 0 7}{space 1}{text:( 1)}{space 1} {res}[model]PC + [model]_cons = 0{p_end}

{txt}{hline 13}{c TT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{col 14}{c |}      Coef.{col 26}   Std. Err.{col 38}      z{col 46}   P>|z|{col 54}     [95% Con{col 67}f. Interval]
{hline 13}{c +}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{space 9}(1) {c |}{col 14}{res}{space 2}  3.99562{col 26}{space 2} .3826609{col 37}{space 1}   10.44{col 46}{space 3}0.000{col 54}{space 4} 3.245618{col 67}{space 3} 4.745621
{txt}{hline 13}{c BT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}

{com}. lincom _cons + OE // WTP in OE treatment

{p 0 7}{space 1}{text:( 1)}{space 1} {res}[model]OE + [model]_cons = 0{p_end}

{txt}{hline 13}{c TT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{col 14}{c |}      Coef.{col 26}   Std. Err.{col 38}      z{col 46}   P>|z|{col 54}     [95% Con{col 67}f. Interval]
{hline 13}{c +}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{space 9}(1) {c |}{col 14}{res}{space 2} 3.671231{col 26}{space 2}  .478955{col 37}{space 1}    7.67{col 46}{space 3}0.000{col 54}{space 4} 2.732497{col 67}{space 3} 4.609966
{txt}{hline 13}{c BT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}

{com}. // convert ln(std dev) into std dev
. nlcom exp([lnsigma]_cons+[lnsigma]DB) - exp([lnsigma]_cons) // STD DEV of WTP for DB (relative to SBC)

       {txt}_nl_1:  {res}exp([lnsigma]_cons+[lnsigma]DB) - exp([lnsigma]_cons)

{txt}{hline 13}{c TT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{col 14}{c |}      Coef.{col 26}   Std. Err.{col 38}      z{col 46}   P>|z|{col 54}     [95% Con{col 67}f. Interval]
{hline 13}{c +}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{space 7}_nl_1 {c |}{col 14}{res}{space 2} .6008835{col 26}{space 2} 1.035791{col 37}{space 1}    0.58{col 46}{space 3}0.562{col 54}{space 4} -1.42923{col 67}{space 3} 2.630997
{txt}{hline 13}{c BT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}

{com}. nlcom exp([lnsigma]_cons+[lnsigma]PC) - exp([lnsigma]_cons) // STD DEV of WTP for PC (relative to SBC)

       {txt}_nl_1:  {res}exp([lnsigma]_cons+[lnsigma]PC) - exp([lnsigma]_cons)

{txt}{hline 13}{c TT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{col 14}{c |}      Coef.{col 26}   Std. Err.{col 38}      z{col 46}   P>|z|{col 54}     [95% Con{col 67}f. Interval]
{hline 13}{c +}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{space 7}_nl_1 {c |}{col 14}{res}{space 2} .1805643{col 26}{space 2} .8894437{col 37}{space 1}    0.20{col 46}{space 3}0.839{col 54}{space 4}-1.562713{col 67}{space 3} 1.923842
{txt}{hline 13}{c BT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}

{com}. nlcom exp([lnsigma]_cons+[lnsigma]OE) - exp([lnsigma]_cons) // STD DEV of WTP for OE (relative to SBC)

       {txt}_nl_1:  {res}exp([lnsigma]_cons+[lnsigma]OE) - exp([lnsigma]_cons)

{txt}{hline 13}{c TT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{col 14}{c |}      Coef.{col 26}   Std. Err.{col 38}      z{col 46}   P>|z|{col 54}     [95% Con{col 67}f. Interval]
{hline 13}{c +}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{space 7}_nl_1 {c |}{col 14}{res}{space 2} 1.062122{col 26}{space 2} .8947812{col 37}{space 1}    1.19{col 46}{space 3}0.235{col 54}{space 4}-.6916173{col 67}{space 3} 2.815861
{txt}{hline 13}{c BT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}

{com}. nlcom exp([lnsigma]_cons) // STD DEV of WTP for SBC

       {txt}_nl_1:  {res}exp([lnsigma]_cons)

{txt}{hline 13}{c TT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{col 14}{c |}      Coef.{col 26}   Std. Err.{col 38}      z{col 46}   P>|z|{col 54}     [95% Con{col 67}f. Interval]
{hline 13}{c +}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{space 7}_nl_1 {c |}{col 14}{res}{space 2} 3.415729{col 26}{space 2} .8219839{col 37}{space 1}    4.16{col 46}{space 3}0.000{col 54}{space 4}  1.80467{col 67}{space 3} 5.026788
{txt}{hline 13}{c BT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}

{com}. 
. 
. ***Bivariate interval regression for DB data 
. biprobit (ChoiceDB1 = CostDB1) (ChoiceDB2 = CostDB2)

{txt}Fitting comparison equation 1:

{res}{txt}Iteration 0:{space 3}log likelihood = {res:-62.984698}  
Iteration 1:{space 3}log likelihood = {res:-52.799695}  
Iteration 2:{space 3}log likelihood = {res:-52.777099}  
Iteration 3:{space 3}log likelihood = {res:-52.777098}  
{res}
{txt}Fitting comparison equation 2:

{res}{txt}Iteration 0:{space 3}log likelihood = {res:-63.682557}  
Iteration 1:{space 3}log likelihood = {res:-60.224679}  
Iteration 2:{space 3}log likelihood = {res:-60.222015}  
Iteration 3:{space 3}log likelihood = {res:-60.222015}  
{res}
{txt}Comparison:    log likelihood = {res}-112.99911

{txt}Fitting full model:
{res}
{txt}Iteration 0:{space 3}log likelihood = {res:-112.99911}  
Iteration 1:{space 3}log likelihood = {res:-107.37949}  
Iteration 2:{space 3}log likelihood = {res:-106.15782}  
Iteration 3:{space 3}log likelihood = {res:-106.04359}  
Iteration 4:{space 3}log likelihood = {res:-106.04272}  
Iteration 5:{space 3}log likelihood = {res:-106.04272}  
{res}
{txt}Seemingly unrelated bivariate probit{col 49}Number of obs{col 67}= {res}        92
{txt}{col 49}Wald chi2({res}2{txt}){col 67}= {res}     27.74
{txt}Log likelihood = {res}-106.04272{txt}{col 49}Prob > chi2{col 67}= {res}    0.0000

{txt}{hline 13}{c TT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{col 14}{c |}      Coef.{col 26}   Std. Err.{col 38}      z{col 46}   P>|z|{col 54}     [95% Con{col 67}f. Interval]
{hline 13}{c +}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{res}ChoiceDB1    {txt}{c |}
{space 5}CostDB1 {c |}{col 14}{res}{space 2}-.4526564{col 26}{space 2} .1223481{col 37}{space 1}   -3.70{col 46}{space 3}0.000{col 54}{space 4}-.6924542{col 67}{space 3}-.2128586
{txt}{space 7}_cons {c |}{col 14}{res}{space 2} 1.823541{col 26}{space 2} .4758587{col 37}{space 1}    3.83{col 46}{space 3}0.000{col 54}{space 4} .8908755{col 67}{space 3} 2.756207
{txt}{hline 13}{c +}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{res}ChoiceDB2    {txt}{c |}
{space 5}CostDB2 {c |}{col 14}{res}{space 2}-.1701856{col 26}{space 2} .0714907{col 37}{space 1}   -2.38{col 46}{space 3}0.017{col 54}{space 4}-.3103047{col 67}{space 3}-.0300664
{txt}{space 7}_cons {c |}{col 14}{res}{space 2}  .601277{col 26}{space 2} .3049443{col 37}{space 1}    1.97{col 46}{space 3}0.049{col 54}{space 4} .0035972{col 67}{space 3} 1.198957
{txt}{hline 13}{c +}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{space 5}/athrho {c |}{col 14}{res}{space 2} 1.486286{col 26}{space 2} .5235084{col 37}{space 1}    2.84{col 46}{space 3}0.005{col 54}{space 4} .4602289{col 67}{space 3} 2.512344
{txt}{hline 13}{c +}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
         rho {c |}{col 14}{res}{space 2} .9026391{col 26}{space 2}  .096976{col 54}{space 4} .4302708{col 67}{space 3} .9869386
{txt}{hline 13}{c BT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
LR test of rho=0: chi2({res}1{txt}) = {res}13.9128                       {txt}Prob > chi2 = {res}0.0002
{txt}
{com}. nlcom -[ChoiceDB1]_cons/[ChoiceDB1]CostDB1 // Mean WTP1

       {txt}_nl_1:  {res}-[ChoiceDB1]_cons/[ChoiceDB1]CostDB1

{txt}{hline 13}{c TT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{col 14}{c |}      Coef.{col 26}   Std. Err.{col 38}      z{col 46}   P>|z|{col 54}     [95% Con{col 67}f. Interval]
{hline 13}{c +}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{space 7}_nl_1 {c |}{col 14}{res}{space 2} 4.028533{col 26}{space 2} .3168479{col 37}{space 1}   12.71{col 46}{space 3}0.000{col 54}{space 4} 3.407523{col 67}{space 3} 4.649544
{txt}{hline 13}{c BT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}

{com}. nlcom -[ChoiceDB2]_cons/[ChoiceDB2]CostDB2 // Mean WTP2

       {txt}_nl_1:  {res}-[ChoiceDB2]_cons/[ChoiceDB2]CostDB2

{txt}{hline 13}{c TT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{col 14}{c |}      Coef.{col 26}   Std. Err.{col 38}      z{col 46}   P>|z|{col 54}     [95% Con{col 67}f. Interval]
{hline 13}{c +}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{space 7}_nl_1 {c |}{col 14}{res}{space 2} 3.533067{col 26}{space 2} .7451519{col 37}{space 1}    4.74{col 46}{space 3}0.000{col 54}{space 4} 2.072596{col 67}{space 3} 4.993538
{txt}{hline 13}{c BT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}

{com}. nlcom -1/[ChoiceDB1]CostDB1 // SD WTP1

       {txt}_nl_1:  {res}-1/[ChoiceDB1]CostDB1

{txt}{hline 13}{c TT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{col 14}{c |}      Coef.{col 26}   Std. Err.{col 38}      z{col 46}   P>|z|{col 54}     [95% Con{col 67}f. Interval]
{hline 13}{c +}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{space 7}_nl_1 {c |}{col 14}{res}{space 2} 2.209181{col 26}{space 2} .5971174{col 37}{space 1}    3.70{col 46}{space 3}0.000{col 54}{space 4} 1.038853{col 67}{space 3}  3.37951
{txt}{hline 13}{c BT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}

{com}. nlcom -1/[ChoiceDB2]CostDB2 // SD WTP2

       {txt}_nl_1:  {res}-1/[ChoiceDB2]CostDB2

{txt}{hline 13}{c TT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{col 14}{c |}      Coef.{col 26}   Std. Err.{col 38}      z{col 46}   P>|z|{col 54}     [95% Con{col 67}f. Interval]
{hline 13}{c +}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}
{space 7}_nl_1 {c |}{col 14}{res}{space 2} 5.875939{col 26}{space 2} 2.468334{col 37}{space 1}    2.38{col 46}{space 3}0.017{col 54}{space 4} 1.038093{col 67}{space 3} 10.71378
{txt}{hline 13}{c BT}{hline 11}{hline 11}{hline 9}{hline 8}{hline 13}{hline 12}

{com}. testnl (-1/[ChoiceDB2]CostDB2 = -1/[ChoiceDB1]CostDB1) (-[ChoiceDB2]_cons/[ChoiceDB2]CostDB2 =  -[ChoiceDB1]_cons/[ChoiceDB1]CostDB1) // Test: equal means and SDs

{col 3}{txt}(1){res}{col 8}{bind:-1/[ChoiceDB2]CostDB2 = -1/[ChoiceDB1]CostDB1}
{col 3}{txt}(2){res}{col 8}{bind:-[ChoiceDB2]_cons/[ChoiceDB2]CostDB2 = -[ChoiceDB1]_cons/[ChoiceDB1]CostDB1}

{txt}{ralign 22:chi2({res:2})} =  {res}      2.21
{txt}{ralign 22:Prob > chi2} =  {res}      0.3319{txt}

{com}. 
{txt}end of do-file

{com}. log close
      {txt}name:  {res}<unnamed>
       {txt}log:  {res}D:\Research\Elicitation effects\VZ analysis (log).smcl
  {txt}log type:  {res}smcl
 {txt}closed on:  {res}28 Sep 2019, 15:19:34
{txt}{.-}
{smcl}
{txt}{sf}{ul off}